Slicing or hooking my drives...

 Few months ago, my drives was superb, very straight and long, reaching a average of 270-280 yards then out of nowhere i started to hook it slightly left but i was reasonably happy because all i had to do was align myself for it to go straight to where i wanted it.

 For the past 3 weeks, i have started fading/slicing my drives, i have tried to find out the causes but have no idea what to do to stop myself from slicing. Whenever i tried to recitfy the problem, i end up slicing it even more or hook it really badly. The thing is, i'm not as aggressive as i used to be few months ago, i thought perhaps the composure would help me become more consistent but it seems to have made it worse! I'm not sure what i should say but if you ask me, i'll gladly tell you the answers

 I know some of you will suggest seeing a pro but my pro is on holiday for the next 3 weeks and i got a open championship to compete in at the end of August so i'm not particulary keen on seeing a different pro otherwise they'll change my grip or swing to their preference.

 Any helps would be greatly appreciated! Thanks.

How far can he hit, Jamie - a very long way indeed and way further than what you would consider a long drive. A pity he missed the opportunity to do this when he was a little younger as I am sure he would have been a household name b now.