I made this for a friend for graduation. It wasn't too difficult. You just have to make a bunch of granny squares in whatever colors you choose. Then sew together and put an edge around the outside to finish.
It was time consuming, but it was worth it!
I was given a job by my Mum, she wanted a blanket to put along the bottom of the bed in the spare room. I had to have a fair bit of blue in it but apart from that I was given free rein