Textured material editing

hi everyone,

I want to rotate the texture which i applied to the plane, how can i rotate that in sketchup itself???

right click the surface then from menu select Texture, then position, the pins then are used as labelled.
latter part
"Repositioning textures"

Right click on the face, choose Texture>Position.

Then either move the green pin or right click and choose Rotate and the angle you want.