After the first coats of paint, I give the model an oil wash. Use a Q-tip to pull the oil off.
With flat dry brush, I pull the rest off and then repeat with Q-Tip. Then again with flat brush. I just work the oil into the paint and seams until I'm satisfied with the look.
After 1st oil wash, add decals. Here, I'm painting over the decal to blend it in more to the surface.