LDR and spicing up the relationship?

Hi ladies! So I've been in an LDR for a couple months now and the lack of sex or anything really sexual really sucks. My boyfriend and I were very sexually active before so it's a big change. I don't need the sex and I'll live without it but I miss that side of our relationship. 
Anyways I've been thinking about sending nudes or a picture in my underwear or something like that but I'm nervous. We're well over age so the legal side is fine plus I trust him completely not to show them to anyone. And I know he wouldn't mind them at all because he's asked for one in the past but I said no because I wasn't comfortable. He's never brought it up since and now that we're LDR I'm reconsidering. I just don't know if just sending him one out of the blue is a good idea or if I should talk to him about it first? Are there any dos/don'ts for this type of thing? I've never done anything like this at all so I'm just nervous. 
Any advice would be great! Thank you