The dryer wouldn't start on a regular basis.

I first unplugged the dryer from the wall socket. Then I removed the timer knob by first folding back the rubbery edge with my finger and then popping out the metalic center piece with a flat screwdriver. To remove the knob itself I used needle nose plyers (although just any two pointy objects like pens would work) and pushed the center clip together which releases the knob from the part to be replaced. This clip is the area that sticks out on the new part and reaches from inside the back of the panel to the knob on the front. The circular covering/skirt piece below this just lifted out. I then removed the three screws from the top back of the control panel of the dryer and tilted the panel forward to access the inside. The part being replaced is held in place in three areas. Push down on the plastic piece to then allow the part to be slid to the left and out from under the two other pieces holding it in place. Unplug the wiring by releasing the black housing/socket by lifting it over the plastic lip holding it in place with the assistance of a screwdriver. Mine was really hard to detach but eventually it came off. Don't pull on the individual wires.
Attach the new part to the wires and install it by doing the reverse of the instructions used to get the old one out.
I'm a housewife in my mid 40's with NO experience with this sort of thing. This was really easy and the dryer starts every time now!