Returning to the UK as a visitor after YMS expires

My YMS visa expires in May and I'm planning on leaving the UK before it expires. I want to return to the UK as a visitor though for a few months.

Is there a certain amount of time I must be away before I can return as a visitor?

Also, do I have to return to Canada first before I can return to the UK as a visitor, or can I go to another European country and then go back to the UK as a visitor?

Any advice would be greatly appreciated! Thanks!