I built my raised bed last week! It didn't take too long. I laid out lengths of weed barrier over the space where the bed was going, with a half foot of extra space on each side. I removed all the grass beneath the bed and around it. Some I had removed last year when I was planting right in the ground. We connected all of the sides first, and then put in some posts on the outside to help keep it in place.
Last year I lost a lot of my small potential harvest to slugs! So keeping slugs out is a major goal this year.