BLOWJOBS!!!!! Advice please !!

Okay so I have been talking/sexting/exchanging nudes with this guy for about 3 months now and the other day when we were talking I asked him if he was going to this event called relay for life (which is an overnight relay thing and a lot of high schools have teams in it ) he said yes, so I asked if he wanted to meet up, he also said yes, and at that moment in time I was feeling a bit horny so I asked if he would like a BLOWJOB and he said yes, now after a couple of days I don't regret it but I have never given a blowjob before so I would like some advice ??