Its not hard. Conceptually I put a fulcrum where I want it to bend (usually 1/8" aluminum sheet just sticking out of a vise) and smack the spindle on the end with something that will not damage the taper (mallet or dead blow hammer for example). Then I put the spindle a pair of widely spaced V blocks as support under the straight shaft and rotate the spindle under a dial indicator to quantify the amount of bend left. Do not hit it very hard - it is easy to over bend the spindle. But as Cobbler said, watch some videos.
