When i first leared F2L i was EXTREMLY SLOW!!! like 2 1/2 minutes (my beginers record was 42 sec) so i just stopped, but then i learned 2 look oll and 2 look pll and i got faster. then i told my self'What is i do the Fridrich method F2L for the next 2 weeks'...so i did and after that it's history. All you got to do is keep practicing untill you got the hang of it... then practice some more! :D
Hope this helped!!!!!