For a nice bendy handled bow, take your 68", hickory board and make it 1-3/4" wide. Rip it to just over 1/2" thick. From center, mark 4" on both limbs. A straight taper from there to the center of the end and you will have your profile. Cut nocks 1" from the tip for a 66" NTN bow. It should be pretty well tillered assuming a good board and decent wood removal. Tweak tiller and shoot away. It'll be around 50# at 28".
I just made one that as 72" (70" NTN) from red oak this week. It finished at 40# at 28" and follows the string by 1.5". It shoots nice after I narrowed the last 8" of the limbs to about 3/4". Kind of Holmegard like.
Have fun. make bows.