I started increasing my weight training recently to build up my strength and tone my muscles.
Oh, nice! Did you start lifting heavier weights, or did you come up with a new routine?
I have been progressively increasing the weight and then I do also alternate the variety of exercises I use to keep my muscles guessing. It really gives me good results. I just went up by 5 more pounds.
Very cool! How often do you increase the weight?
About every 2 weeks as long as I'm handling it well.  I also use body weight exercises on alternate days to help with flexibility, endurance, speed, and power.  
Very nice! Sounds like you are building your body up well. Do you take any supplements?
I do take Vitamin B12 and Amla powder for muscles recovery, but otherwise I make sure to get all my vitamins, minerals, fiber, fatty acids, and amino acids from fruits, vegetables, nuts, and seeds. It works well for me.