I simply use pantyhose over the end of my siphon tube, secured by a rubberband sterilized in vodka. Boil the pantyhose first for approx. 10 minutes to sterilize. Use tongs to fetch them out of the boiling water and hold while you insert the tube. Put a pair on both ends of the tube if you want to be safe. If the beer has a lot of hops in the fermentation vessel, you may only be able to put the pantyhose over the end that goes into your bottling bucket, as the other end may clog with pantyhose on it. Leave the pantyhose slightly baggy on the end thats in your botting bucket because sediment/hops will come through and begin to fill the hose up.
Its not the most perfect way, but hope this helps.