After Sara The Physio (I think) was nagging me a few weeks ago I have been practicing standing straight up, not doing it to one foot forward and one half the way back which I had to do since I learned to stand up again.
Yes, it is much more difficult but practice makes it easier. I need to move my bum slightly forward in my chair but then I can do it with no hands holding on etc, it is much more like a normal standing up action