I was a costume major in college and thus I can say from painful experience that it's not that easy to get liquid latex out of fabric.
Oil breaks down the latex but can wreck clothing. You have to apply the least amount of oil to the latex stain (often with a Q-tip) and try and peel it off the fabric fibers (tweezers work well if it's really clinging). Mineral oil can work, so can petroleum jelly (aka Vaseline) but try and keep as much of that as possible off the fabric.
As soon as you can after you remove the latex, you have to wash the garment to get the oil off of it, or it will wind up leaving a stain of its own.