First of all, be honest with your boyfriend that you’re nervous about making love in the light, but you’re going to do it — one way or another. If he understands that this is a step for you, my guess is that he’ll be understanding of your reticence.
Second, try being naked when he’s not there, in the light. Walk around your house naked. Sleep naked when he’s not there. Go into your kitchen and fix breakfast for yourself naked. If you can become more comfortable with yourself naked, it may be easier for you to be comfortable with him naked.
Third, ask for his help. Tell him you really want to do this for him, but you can’t just plunge right in — you’re going to need a coach, and you’d like it to be him. He may consider this not only to be a very sexy role, but a sign of your trust, and a building block to intimacy.
See if with those three tools, you can then begin to try making love with the lights on — with the understanding that at any point, if it’s too much for you, you get to turn them off. Only each time, try to go a little further with the lights on. You may only make it for a minute or two the first time. The second time, maybe five minutes. The third time, maybe a little more.
You don’t have to assume this burden alone. As your partner, it’s not just his privilege to help you over these steps, it’s his responsibility. There are sex acts that one person in a relationship is more comfortable with than the other person, all the time. The journey of sex and intimacy is about seeing what works for the two of you together.
And don’t forget that just because he’s older than you are doesn’t mean he’s better, more experienced, or right about sex all the time. Age is just a number, and you may find that there are things he’s hesitant to try — in the bedroom or out of it — that are natural to you.