If you're talking pop-up blind and not natural blind, I do this with a recurve. Think it will work for a longbow as well. I tie a loop in a piece of parachute cord and tie the cord to one of the overhead blind roof braces/rods. I then set the bow's lower tip on the ground in front of or to the side of me and put the upper limb tip in the loop, with the bow leaning forward a little.
Might need to adjust the position of the parachute cord up or down and/or side to side to get it where I want, but very convenient, quiet and easy to use when it's set up. When a critter comes by, I just grab the bow and lean it back and the loop falls from the top limb tip. Give it a try if you're using a pop-up.