how do i get up on the roof? I jumped up the bricks until i was on the small red ledge then jumped right onto a small roof below a window but i can't get across to the left above where i came up because when i jump left i come to a corner and keep falling off.

You need to quick-jump up this part - jump across to the ledge you keep falling off and keep tapping jump as soon as you touch it. You won't get across by just jumping once and hoping you don't slide off.