Getting paint on your jeans is in an inevitable part of the painting process. "Goo Gone" and "Goof Off" are two wonderful products that can almost always remove the stain and restore your jeans.
Removing the Stain
Remove fresh paint as soon as you can using something with a hard edge such as a putty knife or butter knife.
Apply a few drops of "Goo Gone" or "Goof Off" to a clean, dry, white cloth.
Rub the cloth gently onto the stain and work out the paint as best you can.
Allow "Goo Gone" or "Goof Off" to work into the stain and let it set for about two to three minutes.
Use a putty knife or butter knife to scrape off the paint.
Use soap and water to clean the stained area. Blot area with a clean white cloth.
Repeat steps if necessary.
Launder jeans separately using extra detergent as soon as possible.