Hi guys,I'd like to ask you, how can i make invisible texture?

Don't make completely invisible textures. They suck and ruin the game.

To make invisible sections you have to use alpha channels. Read up on how to do them with whichever image editor you use.

I've got photoshop CS4

Then just make a new layer, delete the default white layer, and BOOM complete invisible texture.

The way you'll know it's invisible is when it looks like there's a white and grey checkered pattern like this:

I made it,thanks!