I tried to go clipless about 3 months after getting on a bike for the first time...after 3 days of many, many falls I went back to my beloved BMX pedals for another 6 months. The second attempt went much better, and indeed I've only fallen over twice since then, doing something silly both times

I was also going to spinning class before and during that 6 months break and that really helped I think. The main problem the first time was that I didn't have normal riding stuff in my muscle memory yet and I think adding clipless at the time was just overload for my body.