I personally use a spreadsheet but I'm sure there are better way to do it.
Do you know any good websites/apps to do it?
if trading is better to use the blockfolio in google playstore the more features of the apps .. just read the playstore or download it as you expect that apps. If you're using a gambling calculator you can easily compete with your losses and win but you can not order them to stop gambling. In the gamble when you win you do not stop losing you more and more stops until your capital is not exhausted.