Sometimes operating according to certain criteria of your own is not so bad, as long as you keep in mind that the main thing is to risk what you are willing to lose, and above all to ensure your operations with a good stop loss, for me that is the main thing, When we take into account that we can do many things by following some advice, it is not bad, but it is good to have our own criteria, at least I obtained it by reading some books, which have taught me many things about the market and how it moves in Sometimes, but there are always events that we do not see, and that most of the time we fail.
Based on how you learned those criteria of course. I mean if it is a good one then you are going to be doing fine, but if it is a bad one then you are not going to be making that much profit from it.
I personally do have a system in place and not for leverage but for spot trading and so far I have been doing fine with it, but I failed many many many times before I did anything like this. Sure it is not really a great system if you consider the fact that I am making a profit NOW but it took me losing a lot to reach here. So if you want to do leverage trading you need to be even more careful, losing at leverage doesn't mean a bit of a drop, it means all of your "bet" is gone in that sense.