How would you get semi-gloss paint off of clothing?

If you got water-based paint on them, you might be able to save them if the paint is still wet, but I wouldn't bet the rent on it. If it's oil-based, or if it has dried no matter what kind it is, you're pretty much out of luck. I'd suggest wearing old stuff that you don't mind ruining if you have to paint again. Now you know why painters wear those overalls with tons of paint on them - why ruin another pair?

Getting Gloss Paint Off Clothes

You can get latex semi gloss paint out. Put the clothes in the sink, put mild detergent (I used dish soap) add a little alcohol and a soft bristle brush and scrub lightly. It all came out of my t- shirt. Rinse with warm water while scrubbing.

if it is waterbase and still wet, throw them in the washer and wash several times, until water runs clear, if is oil based or needs paint thinner, it may be a lost cause

If it's dry, it's going to be tough. You can try soaking the spots with rubbing alcohol