Are you talking about making friends with ESTJs, or just warming up to them?
If you mean making friends, here's my suggestion: I'm not sure about other (read: male) ESTJs, but with me, the best way to see my marshmallow center is to show that you care. I'm not necessarily going to be the daring one in friendships, especially in the early stages. If you show that you want to go to that level, and if you and I are compatible, it won't be so hard.
If you mean becoming a friendly acquaintance, I'd suggest making jokes, and pointing out shared interests. ESTJs are an EXTREMELY varied bunch, interest-wise (one ESTJ's passion can be another's taboo), so I wouldn't suggest one particular thing over another. (There's no reliable ESTJ conversation topic, like there might be with NTs [science, usually]). The "show that you care" thing applies here, too, to a lesser degree, since it's hard for two people to be friendly when one of them doesn't care what the other has to say.