First things first, PowerPoint isn't ideal software for graphic design (yes, I know erstwhile good mocks have originated from it but you have to have a certain amount of skill to know what you can and can't get out of it and be going for a certain, simplistic feel). If you haven't access to Photoshop, try free alternatives such as gimp.net. There's a lengthy learning curve to all of them but at least you would be starting in the right place.
As per broadcast standards, mocks should be presented in 16:9 (usually at a resolution of 640x360 for forum layout reasons) and adhere to safe areas where necessary. It is all in the
Guide to Mocking thread, which you should read before posting, which highlights *why it needs to be sticky*.
The mock itself isn't great but you're using limited software so I'll let you off. Always look to see what the channel you're mocking are doing currently; if yours plainly isn't to a similar standard or an improvement (whether in concept or execution), don't bother posting.
