Sometimes the hub can be stuck on the CV shaft, so you might have a job there. If it comes off ok, then the joint has to be popped off the shaft. There's only a thin C-clip holding the two together and as long as the joint/shaft are in a straight line, then a whack on the back of the joint cup should see them seperate ( it might take a few goes though). Cut the old boot off, clean up, put the new boot on the shaft and slide it too far back for now. Make sure the C-clip is in it's slot (you may have a new one supplied with the boot kit). Locate the CV joint on the splines of the driveshaft in a straight line, then whack it with a mallet and it should click on (check it by trying to pull it back off again). Pull the boot towards the cup, fill with CV grease, then locate the boot (it might be a tight fit). Attach the boot at both ends with cable ties/wire strap, and reassemble.
Les.