Mostly a reader, rarely post, but I figured I would share how I pick an online casino these days. After a few bad experiences I stopped going by ads alone.
Licence comes first for me: see which authority is listed in the footer, and whether they actually accept players from your country. Next come deposits and withdrawals: card, e-wallets and bank transfer should all be there, and the withdrawal limits need to be written clearly.
Bonuses are the tricky part. Read the wagering and the max bet rule, and the bonus usually expires in a week or two. A good recent review that covers all of this can be found here official site before you deposit anything.
Most of my sessions are on mobile, and a good site loads fast and does not log you out every five minutes. Support matters too: slow or scripted answers usually mean trouble later.
That is about it. Set a budget and stick to it.