How to Give a Promise Ring
To give a promise ring as a pre-engagement ring, try presenting it at a significant location, like the restaurant where you had your first date. You can also try planning a day of fun activities such as a hike ending in a picnic. Then, present the ring to your partner during the picnic with a declaration of how much they mean to you, and the specific commitment you're making to them. Alternatively, give them the ring at home or at another private location if your significant other isn't comfortable with public displays.
Know the purpose and predict the recipient's reaction. If you are giving a promise ring as a sign of friendship, or to someone you've only recently been dating, pick something simple and inexpensive. If your partner is hoping for a marriage proposal, either use a less culturally significant piece of jewelry or make the decision to exchange promise rings in advance so you don't disappoint them with a misinterpreted surprise. Select something the recipient will wear. If they don't wear rings, place the ring on a necklace chain or use a different "promise gift". Try to find out their ring size by temporarily "stealing" a ring and having a jeweler measure it. If the recipient has a job or hobby that could wear down or scratch the ring (such as construction or rock climbing), select a hard material such as titanium. If the ring is a promise to become engaged in the future, or a "wedding ring" for a couple that doesn't plan on getting married, select a ring that fits on the ring finger of the left hand, or wherever your partner plans to wear a wedding ring. For most other promise rings, select a ring that fits on any other finger. (Often the ring finger of the right hand, which can be a different size than its left counterpart.) Examine posy rings. Also known as poésy rings, these are metal bands with a love poem, promise, or other inscription engraved on the inside surface, next to the wearer's skin. These are an excellent choice, since they are usually distinguishable from wedding bands and can literally display a promise. A jeweler can help you make your own posy ring by engraving a personal message from you to the recipient. Many posy rings quote Bible verses or other Christian inscriptions, but the tradition has expanded to secular society or other religious couples. Consider Claddagh rings. These rings originate in Ireland and depict two clasped hands holding a heart. This visual sign of love or friendship serves as a warm reminder of commitment. Ask about customization. Most jewelers are willing to design or customize a ring for you by adding special elements, such as engraved messages or unique, significant decorations. Consider engraving the same promise you will make verbally. Think about other options. A promise ring shouldn't be so expensive or elaborate that it is mistaken for a wedding ring, but a ring with special significance adds extra weight to the promise. Consider a ring with the recipient's birthstone, or a custom engraving. If you can't afford to buy jewelry, or if the recipient enjoys less fancy gifts, make your own jewelry or other gift. Use a material or object with special significance in your relationship if possible. A necklace, earring, or other piece of jewelry is just as good a symbol. This option is especially wise when giving the promise to a partner who is eager for a marriage proposal; you don't want to mislead them. If you're having trouble deciding, or simply like this idea, ask the recipient if they would like to exchange promise rings, then talk together about selecting a matching pair. Find out their ring size. If it's going to be a surprise, it shouldn't be too obvious you're trying to find out. Consider measuring other rings that already fit, or ask friends and family for help. If you're still unsure, get a ring that can be resized. Pick a significant day. A promise ring might be appropriate as a gift on Christmas, Valentine's Day, or the recipient's birthday. If you're in a relationship, your annual anniversary of dating could be an excellent choice. Present the ring at a significant location. Go to the restaurant you had your first date, the concert hall where you first met your friend, or any place the two of you made a happy memory together. Keep in mind the kind of person the recipient is: some people are comfortable receiving the ring in a crowded place while others prefer somewhere more private. Don't overdo it. This is not a wedding proposal. You don't need to hire a skywriter or organize a flash mob. Consider making it a scavenger hunt. Leave a written clue somewhere the recipient will find it, and have it hint at the location of the next one. Think of clues that only you two can understand. At the end of the chain, you'll be there to present the promise ring. This kind of elaborate setup can be fun or romantic, but be sure the recipient will react well when they find out it is a promise ring. It may be too early in the relationship for a sign of serious commitment, or conversely your partner may be expecting a proposal. Keep the clues simple and obvious; the point isn't to confuse them! If the target enjoys puzzles, you can make the clues harder, but have you or a friend follow them sneakily to run in and give them another hint if they get stuck! Plan a day of activities. A fun day spending time together is a great way to lead up to a special moment. Consider a hike ending in a picnic, or make a home cooked meal. Organize it in advance to avoid unexpected guests at home or an empty fuel tank on your way back from hiking. If something unexpected ruins your day together, plan to present the ring a different day. Think about slipping the ring somewhere surprising. Hide the ring somewhere the future wearer will eventually find it, such as under their pillow or inside their lunchbox. This can be part of another setup or stand on its own, depending on how much you want to build up the moment. If you won't necessarily be there when they find it, include your promise in writing and follow it up with a personal declaration. Show them the ring. Present the ring or other "promise gift" simply by opening a gift box and showing it to her; you don't want it mistaken for a marriage proposal. If you left it somewhere secret for the recipient to find, give them a moment to take it in. Declare your promise. If there is a specific commitment you're making (such as sobriety or fidelity), announce this clearly as you give the ring. Prepare a few words in advance if you don't want to come up with them spontaneously. Don't over-promise. Don't say you plan to marry the recipient someday unless you are prepared to follow through. Make your intentions clear, even if they are as simple as a desire to show your love or support. A quote from a favorite poem or song can lend your declaration extra emotion, but make sure some of the words are your own. Compose a short song or poem (optional). If you play music, sing, or write poetry, composing a piece that says how you feel can be a touching way to communicate the promise. Include personal details. Tell the person how much they mean to you in your own words. Reference specific qualities you admire and specific happy memories to avoid falling into cliché. Be yourself. You know your relationship with the recipient better than wikiHow does. If the two of you would find meaning in something goofier than described here, or you know the recipient would love a ten-minute sonnet recitation, go with it. Place the promise ring on any finger. Most people wear it on the left hand on the middle finger or on the ring finger of the right hand. Most recipients won't want it to be confused with an engagement ring, so stay away from the ring finger on the left hand. Of course, if you are using a different piece of jewelry or other gift, place it in the appropriate spot or hand it to them formally. 
Know the purpose and predict the recipient's reaction. Select something the recipient will wear. Examine posy rings. Consider Claddagh rings. Ask about customization. Think about other options. Find out their ring size. Pick a significant day. Present the ring at a significant location. Don't overdo it. Consider making it a scavenger hunt. Plan a day of activities. Think about slipping the ring somewhere surprising. Show them the ring. Declare your promise. Compose a short song or poem (optional). Include personal details. Be yourself. Place the promise ring on any finger. 