There are many variations for this song, this is one of them. It's played really slow and with  
kind of an awkward strumming pattern 



E | - - - -3- -3- -3- -3- -3- -3- -3- -3- -3- -3- -3- -3- -3- -3- -| E 
B | - - - -3- -3- -3- -3- -3- -3- -3- -3- -3- -3- -3- -3- -3- -3- -| B 
G | - - - -0- -0- -0- -0- -0- -0- -0- -0- -0- -0- -0- -0- -0- -0- -| G 
D | - - - -2- -2- -2- -0- -0- -0- -0- -2- -2- -2- -2- -2- -2- -2- -| D 
A | - - - -2- -2- -2- -2- -2- -2- -2- -3- -3- -3- -0- -0- -0- -0- -| A 
E | - - - -0- -0- -0- -1- -1- -1- -1- -0- -0- -0- -0- -0- -0- -0- -| E 

You keep on repeating this for all the verses and most of the course until the last Gimme More 
Where you play an "A" and then a "C" so that its: 
                                                                                     A           C 
Gimme Gimme More Gimme More Gimme Gimme Mooorrrreeee 
Play around with it a bit and see what sounds best! 
I tabbed this off a Youtube Video link is below so watch and listen to how he does it. 

                                               Britney Spears- Gimme More 

It's Britney Bitch 

Everytime they turn the lights down 
Just wanna go that extra mile for you 
Public display of affection 
Feel's like no one else in the room 

We can get down like there's no one around 
We'll keep on rockin (Keep on Rockin) 
We'll keep on rockin (Keep on Rockin) 

Cameras are flashing my way dirty dancing 
They keep watchin 
Keep watchin 
Feel's like the crowd is saying 

                                                             Chorus 
Gimme gimme more 
Gimme more 
Gimme gimme more 
Gimme gimme more 
Gimme 
Gimme gimme more 
Gimme gimme more 
Gimme more 
Gimme gimme more 
Gimme gimme more 
Gimme 
Gimme gimme more 

Center of attention 
Even when they're up against the wall 
You got me in a crazy position 
If you're on a mission 
You got my permission 

We can get down like there's no one around 
We'll keep on rockin (Keep on Rockin) 
We'll keep on rockin (Keep on Rockin) 
Cameras are flashing my way dirty dancing 
They keep watchin 
Keep watchin 
(Feel's like the crowd is saying) 
                                                                Chorus x2