I had my right knee replaced 2 years ago, and my left knee done 8 months ago. I do floor exercises regularly and here is how I get up - Imagine sitting with your legs stretched out straight in front of you. Bend the knee of your better leg and cross it over the other leg. Twist your upper body to the back, putting your hands on the floor and using a push up motion to hold your upper body steady while you rotate your bad leg backside up. Your arms hold you steady while you get both legs out with toes on the ground, then walk your hands back toward your feet until you can rise from the waist. I realize this may not work if you don't have enough upper body strength to support your body weight, or if it's too close to surgery and your bad knee has not enough bend yet. I am 73, 5'4" and weight at 170. I did often have to drag myself to a sofa to get holding support before my left knee regained some bend. I would like to mention I do a lot of gardening=weeding and though kneeling is not comfortable, it can be done. I use a three or four inch thick foam boating safety cushion, and try to keep most of the pressure on the lower area below the knee, not the kneecap itself. It sure was easier before I had the 2nd knee done! If you don't yet have good flexion, this may be difficult. It is very helpful to keep up some of the strength and flexibility exercises that your PT person gives you, even long after you are done with PT. I still use our stair steps to do a few short minutes of pushing my flexion limits, and doing the one knee stair dips for strength.