My first suggestion is by collect call to whatever correctional institution he might be staying in. Then perhaps a letter since I hear that cats in jail love reading letters since all those books in the library are on some non-sense.

Now if you mean romantically, as in, "how do I let this thug know that I love him and want to be with him?", then it's a new ballgame altogether. See, to get a thug, you have to get to the essence of thugness, his thugnificence, if you will. All thugs have it; it's a little easier to reach in different thugs.

Find out what his interests are. If he's into burglary and grand larceny, find out about expensive items that he fancies and discuss with him the finer points of such items. If he's into shootings and things that thugs typically get credit for, maybe learning about different types of guns would help. The point is, you've got to his core. Now, this might seem odd, but most thugs are better read than given credit for. Most of the books they read are about gaining power like SunTzu's The Art of War, but hey, books are books. So perhaps you find out what things interest him on an academic level and get him some books for you all to discuss.

One of the main things you need to do to reach a thug is show him how loyal you are. The ride or die mantra that all thug chicks aspire to is a very real thing. Know it and practice it.

And if all else fails, just watch The Wire and take notes and then go talk to your thug about it and a love connection will be established.