anyone knows how to make a material glow? .-. like a bulb or a tv.

You can use the "model unlit" or "world unlit" material type to get a global illumination effect to just that material.

thanks saje one more question. do you know whats worst, having a big side brush with texture or making many brushes to put caulk in the hidden part .-. do you know what i mean?

One big side brush would most likely be better as the game doesn't have to take account for multiple brushes. As long as you are still caulking it in the correct places.