I did my quilt slightly differently, as I didn't have a Jelly Roll. I cut four 2.5" x WOF strips from 11 different fabrics (44 total pieces), so my quilt ended up wider since I had 4 extra strips- it is about 60 in x 60 in.
One thing I noticed most tutorials tell you to do is to make sure that your super long beginning strip is not twisted. There is NO need to do this. Just make sure the fabric approaching the needle is not twisted- the twist will go to the end (where mine was SUPER twisted) but you have to cut that anyway, then the twist disappears once you make the cut.
I did this top in under 3 hours- from cutting the strips, to sewing together the giant strip, to assembling the top.