First time bj need tips/advice!

So I have been with my bf a year nearly, he never forced me into anything sexual at all it was when I was ready which i love💖.I recently lost my virginity to him 2 1/2 months ago, and he has mentioned bjs and since I was brought up to not do anything out of marriage (my mums religious) I didn't do anything. So now that im with my bf I lost my virginity too I want to do it. (im 19) she's okay with it all now👏but tells me to be careful... So what should I expect from doing it, any tips and advice? And do you do/do not do it any why?

Your answer's would be very appreciated thank u.😘