Should a signature in our posts in any forums include only one url or all which we have?Also should it be simple url or some attractive word or line which when clicked directs to our url?
Your signature is your opportunity to promote yourself. You have a limited amount of space so you have to be reasonably succinct. Most of us pick and choose the sites we promote and change them often.
You are allowed 4 links totalling not more than 350 characters and 3 lines of BBCode. How you dress your links is up to you, but most people use anchor text instead of just a bare URL. Links tend to be for SEO purposes - you'll probably not get too many clicks.