trouble starting

hi all. my golf is struggling to start sometimes. mainly when its warm. it seems like if you dont catch it right its turns over for a very long time before it tryes to fire and then when it does it runs rubbish untill you rev it abit. has anyone had this problem that could help? its a gti by the way

I would start by lining up your timing markings and checking everything is where it's supposed to be. 
It's one of those pain in the ass faults that can be caused by a number of issues. 
Checking the timing is free and a good start, fuel accumulator can cause pressure issues when warm. Try pulling the plug on the 5th injector while you try starting it this will make it continue to inject after the normal 12 seconds. 
Also just have a good check through and make sure the plugs, leads, cap etc are all in good order. 

I had this same problems awhile back and it was down to the injectors being worn and not shutting off completely and dripping fuel into the cylinder bores effectively flooding the engine. Once the engine had cooled and the fuel had evaporated it would start on the button. 

Cheers Chaps i will do all that. I recently changed plugs leads dist cap rotar arm and i have a cam belt to put on so i will check the timing then. I also have an accumilator and 5th injector i could try. I will also look into injectors thankyou