To complete this, you will need 5-10 minutes and the following:
Standard flat head screwdriver
#0 Phillips screw driver
A little common sense
Step 1: Disassembly
Using a standard flathead screwdriver
Gently twist the bottom plug until it releases
Gently remove the plug
Please note the tabs holding the plug in place are soft plastic and look like they will easily break.
Holding the body, push down on the metal shaft. Because of the seal it will take a little effort so I used side of the handle on my screw driver to break the seal and push it down.
Pull the internal assembly out
Step 2: Tighten Metal Shaft
Step 3: Battery
It appears that the battery is glued in place, but I think others have posted instructions on how to remove it.
Step 4: Reassembly
Push the internal assembly back into the body until rubber seal is flush with the top of the body
Push the plug straight in until it snaps into place
Attach brush head
Step 5: Test Your Work
If you really need brushing instructions you probably should not be using a Sonicare
That said, if get all the way to this step and are stuck, click the link below and scroll down to page 7