Based on your financial expertise, provide your response or viewpoint on the given financial question or topic. The response format is open.

How to prevent myself from buying things I don't want
I believe that your dilemma comes from not having clearly defined consequences of buying it. On one side you want it and you can afford it, but on the other side there is nothing solid. Just some vague dislike of spending money and guilt of buying something "useless". You're basically guilt tripping yourself into not buying it, and guilt tripping is always bad. What you need is clear-cut consequence. Something like "I can buy X but then I won't get Y and Z". And for that you need a clearly laid out budget, just to know how much you can spend. Money that go into things that are absolutely required, money that go into various saving plans, etc - and after that you're left with some clear amount that should be spent on making yourself happier. Making yourself happier is not something you should feel guilty about, it's actually one of purposes of life. Making yourself happy is only bad if it's hurting other areas of your life (and even that is relative, because there is always some extent of degradation you're willing to accept or you have already accepted). There is absolutely no point in saving every single penny you can, because that will make you live long and unhappy life and die without enjoying your riches.