First time anal?

My boyfriend finds the thought of anal really exciting and hot but personally it's never really been anything I've thought about doing. Part of me wants to try it for him, but also me, to see if it's something I might possibly be in to but the thought of all the pain sounds unbearable 😩
How did your first time using the backdoor go and any tips on trying it? 
Plus how did you prepare yourself for it?