Before signing up, check the operator on the UK Gambling Commission register...

https://wiki-club.win/index.php/What_Should_a_%E2%80%9CReliable%E2%80%9D_UK_Betting_Site_Ranking_Include_Besides_Bonuses%3F

Before signing up, check the operator on the UK Gambling Commission register and read bonus terms closely, including the 10x wagering cap for licensed operators