how do i clean up my start up disk? i have no idea.

You need to delete files from your internal hard drive which contains the operating system. You can use OmniDiskSweeper to locate large files to delete to make space.

beacham77 wrote:

How do I clean my start up disk?I have no idea. Please help.

Unless the drive is full there is no reason to do so, why do you think you should?