Step 1: find an article on benching on this site (trust me there are PLENTY to choose from)
Step 2: read the article
Step 3: repeat steps 1&2 as many times as needed until the information sinks in (with different articles)
What you should get out of all this is that there are many different ways to set up for benching and you should tweak your set up until you find a position that: A. fits with your goals (strength or mass building) and B. is the most comfortable and works the best for YOU.
What works for one person may be the exact opposite of what works for you.