This is an advanced move. Have someone spot you on a mat before you attempt it on your own. You run the risk to hurt your neck or knees. Hinge back slowly with your abdominal muscles actually pulling you upward so you don't bang down on your knees. Land with wyour shoulders, not head, first. Then lie on the floor starting with shoulders, chest-ribs-back, lower back, butt-hips and legs.
For an even more advanced move, pretend you are making a back bend with no arms. Again, land with your shoulders first. Proceed as above. You will have to bend slightly to one side (whichever is easiest) and land more on one shoulder for about two seconds in both of these moves (before both shoulders are on the ground).
Do one to three moves and advance to sets if and when you can.
Disclaimer: None of the above information can be taken as a substitute for advice from a medical professional such as a physician.
My third book, Pocket Guide to Fitness, is available on www.louizapatsis.com, http://www.authorhouse.com, www.bn.com and http://www.amazon.com. If you look up my name on those Web sites, you will find my other books The Boy in a Wheelchair and Life, Work and Play: Poems and Short Stories.