spinner_jwSrLong time lurker here, so here is what I look at before signing up anywhere. After getting burned once or twice I stopped trusting the big banners.
First thing is the licence: find the licence number and look it up, and whether they actually accept players from your country. After that I look at banking: I want at least one fast e-wallet option, and the withdrawal limits need to be written clearly.
The welcome offer is where most people get caught. Anything above 40x rollover is a red flag for me, and some games count less towards it. A decent independent write-up with the current terms can be found here [url=https://pinshape.com/users/9081227-cryptopickse32ba9]Gamblezen[/url] so you know what you are signing up for.
I play almost only on my phone, and if there is an app I make sure it comes from the official page. Test the live chat before depositing: slow or scripted answers usually mean trouble later.
That is about it. Set a budget and stick to it.