The sock in the skimmer or in front of the return works quite well. Squeeze the sock a couple of times during the day and it will dissolve much faster. I did this in a bucket and had it dissolved in a half a day.

I once tried the sock in the pump basket but it really didn't speed it up much.

If you dump the CYA in the skimmer, it will end up in the filter which is ok but I think it takes longer to dissolve that way.