For putting the copper lug onto the end I use a battery terminal end and "crimp" it on with a blunt chisel and hammer. Its NOT meant to take ANY load at all. Just to help spool on the cable. Always leave 3 wraps on the drum or you will risk pulling off that lug.
I like to run 3/8s cable just for the simple fact that is spools on nicer and doesn't get flat spots as easily. Nothing wrong with 5/16s though.