Do what you do best. If feeder fishing is your strong point then do that, if it is the pole then fish that. Don't worry about beating people if it is your first match, just enjoy the fun and the atmosphere of the match. At the end of the match walk up the bank with the scales and see what people have caught, congratulating any who have beaten you and asking what methods they used, what bait how they fed the swim and where they caught their fish. That way you will be more prepared for the next match.
You never know you may win it or get a place - it happened to me on my first match, I went along with a friend who was a keen match angler and managed 2nd and won my section on the River Wensum on a Boxing Day match with over 100 anglers on the bank. I drew an absolute flier and had I not stopped halfway through for a cup of coffee, a piece of Christmas cake and a walk up the bank chat to others in my section I would have won the match easily. I also swung a lot of roach that fell off, and it didn't worry me in the slightest. Now I would netted them of course. Goodness knows what the experienced match anglers on my section must have thought of me. There were 2 Essex County anglers on my section that day as well! It is quite embarrassing to relate the tale but it is the truth and the records are there to prove it. I was just having a pleasant day's fishing with lot's of fish. I had over 20lb of roach in the end all on a stick float feeding bronze maggot. Today, given the same circumstances, I would have blitzed it, head down, blinkers on and probably had 30lb. I may not have been so chilled out but would have loved to won the match. I have only managed a few section wins since then on that particular match which gets 50 people on it these days.
The main thing is to catch a few fish and enjoy the day.