Sometimes grabbing a free bet can be more complex than is needed, however the Coral website has clear instructions on how to claim your bet and open an account. Easy on the eye, quick and simple - what you want really!
There are certain conditions with the free bet (as with all). You have to place a £5 bet before you can claim your free £20 bet (value of bets will change, is at £20 at the time of writing this review) and you have 7 days to claim it. Also as ever you have to setup an account.