You could by, strap on ladder, climbing sticks...many to choose from today. The cheap bulky way is a ext. aluminum ladder, if you have one...paint it with a flat brown spray bomb.

I made a ladder/game hauler a few years ago. It is square tubing, welded and painted flat brown. I have 2 sections at 6 1/2 feet long, so it fit in the box of my truck with end gate shut. I drilled 2 holes to attach both a wheel and axle or to put the two sections together(with good sized bolts and nut) for 13 feet of ladder. It is a bit heavy but with the wheels it pull easily. I also welded on eye holes to tighten it to the tree with regular chains, but pull straps would probably work. I have it secured in 4 spots. You' ll need to have bracket that allows it to be away from the tree, something I forgot of until I went to test it....ooops. Ssame princple could be used to a 2x4 or 2x2 wood ladder. However it takes some tools and I am not really sure it will save much. When I did it there was nothing on the market other than ladder stands themselves, or screw in steps. Now that is simply not the case, like I mentioned many designs to choose from. I like the climbing sticks by lone wolf, but they are higher in price. Check out www.cabelas.com they have a good variety and will give you some idea on cost.

Why can' t you use screw in steps?