How do you say 'nothing much but hit me up' in Spanish?

Answer 1

It depends on how you mean "hit me up".

If you want the other person to "hit you up" in slang-word the sense of "calling you" or "finding you", then: "Llámame, estoy aburrido" OR "Échame un grito, estoy aburrido" which mean literally: "Call me, I'm bored" OR "Send me a shout, I'm bored."

If you want the other person to physically assault you (i.e. to get hit/punched), then "Gólpeame, estoy aburrido" which literally means "Punch me, I'm bored."

Answer 2

Slang expressions do not translate as well as you might like.

Probably the best translation of the English slang expression "nothing much but hit me up" in the sense of "Nothing much is going on, but call me sometime", would be the Spanish slang expression of "No pasa nada, pero échame un grito ya." The Spanish expression literally means: "Nothing is happening, but send me a shout already."