I killed my first deer ever off the ground with a bow at the ripe old age of 18. There was a group of does coming out in the same corner of an old berry field and I used an old stump as a basis for a makeshift ground blind to take advantage of their routine. IMO the most important thing is concealing your movement with back cover. Having cover in front of you is a no brainer, but when you move without anything behind you, it really exaggerates the movement. Ground blinds are the perfect answer to ground hunting, but a good ghillie suit, slow movement, and plenty of natural cover you can get the job done also. If I am building a natural blind, I start by finding great back cover and working my way forward.
One tip I can suggest is a quality seat that swivels. I use a silicone lubricant to make sure my seat is quiet. Last year I found one at Wal-Mart with a high back that makes a perfect ground blind seat. It is comfortable and I can easily swivel side to side to scan my surroundings, or to get in position for a shot. IMO, being comfortable on the ground is more important than being in the air because I can't get away with as much fidgeting to get comfortable. Also having a bucket to sit things on cuts down on movement leaning down to grab things.