AnswerTo install patio door handles you must first decide where you are going to put the holes in the door to install them then install the handles by screwing them into the holes

Answeryes you can definatly put on new handles by yourself, here's what you do. More often then not these handles are held in place by about 4 screwes, locate were they are and unscrew them to take off the old ones, if you dont have new ones try to get the same basic style so you can match the screw holes otherwise you will have to drill new ones to match your new handles.