First, make sure your model really is supported. Specifically, if the video card isn't supported then you'll have to wait.
I think you have to install YDL last in order to get yaboot configured correctly. You could do it in OpenFirmware afterwards, but that's not for the faint of heart.
If I were you I wouldn't bother with OS 9, unless as merely for Classic. In that case, I'd just put it on the same partition as OS X. On an iBook your space is limited, and I bet you'll be kicking yourself somewhere down the line that you have essentially 1 or 2 unusable GB. You may not experience this, but when I had triple boot going on my iBook G3/800 the colors would be all messed up when I booted into OS 9. Nothing I could do would fix it. Again, YMMV.