that's a difficult subject to be honest, what you don't want to be doing is changing your meta tags all the time as this will highly affect your SEO.
what I would suggest is to use keywords that are relevant to what you do if you get my point, for example> Designing, Cheap Deals, etc
You Can use different meta tags for each page, that's fine as long as you optimise for both, just be careful with that.
I couldn't give you any keywords as such but you can use Google Adwords, check up what keywords are used ans such
hope I helped in some way, if not then nvm all that^