How to prevent baby falling from the bed?

For the past few nights, I have been teaching my 9mth old son how to climb down from the bed. As he's been very active lately and able to climb over the boundaries I set (using bolster, pillows and big blanket) surrounding him while he sleep (er..don't ask me why I didn't put him in baby cot...somehow both my kids prefer sleeping on a queen size bed! :P).

I remembered people describing how their baby fell from the bed ever since I had my first child. However, that did not prevent my daughter from felling down as I have not foreseen her growth to be that fast able to climb over since very young age. 

So this time I start to teach my son earlier...so that he knew the proper and safe way to descend down from the bed!

Somehow this little boy prefer to fly down head first and use his hand to slowly climb down..but that is only working when the bed is lower and would not be useful for higher bed or sofa....

So  I have been teaching him few nights until i think this morning he can understand and uses the right way to climb down...feet first...hehe...

Prevention is better than cure/cries(in my case) right? :)

Cheers!

Molly