you can use bidet sprayer; it's strong spray, attaches to comod. some of them have retractable nossel so it's more hygienic. No need to use your hand. Some of the Japanese toilets have these built in.

http://www.amazon.com/Luxe-MB110-Non-Electric-Mechanical-Attachment/dp/B001KKRCFA/ref=sr_1_1?ie=UTF8&qid=1352952868&sr=8-1&keywords=toilet+water+sprayer