What is Mattwhittaker?
A person who extremely over-exaggerates about practically everything and goes out of his way to make himself look good by constantly lying about things he finds are good achievements or generally good things.
"Ive just drank a crate of lager and im not even pissed and look at you!"
"I could be a pro-footballer, i just choose not to because im too good"
to these you would say
your doing a Mattwhittaker