Are you going early or late May?

I’ve been going WA for the past 10 years last week in May.

You will not need to take loads of bait really, due to the limits in the matches.
The shop pellets are as good as any and fair price, which you can use for fishing the method, which is pretty consistent on most pegs on Twinoaks and Trelawny.
Fish to your strengths and look at what baits have been doing the damage in the most recent festivals.
I always catch a few fish on Paste, but lots use meat or corn, so it really depends what you prefer.

I’ve never taken worm and caster, as found that other baits are just as effective.

Good luck!!

Andys advice is pretty much spot on. Most matches are won on method feeder and micros tight across. Hookbait is not that important, just accurate casting and being on the right peg on the day. If the weather is warm you might catch shallow on wag or pole.
Worm and caster will catch you lots but you may be bitted out with roach.
Dont ignore margins either, feed them for 4 hours before dropping on them late on.
Fish heavy though there are some big lumps down the edge on most pegs.
Take a day out on Bollingey, which is not only in a lovely village near Perranporth, but also a top top lake to bag up. The villiage pub is great too, you will think you are in an angling heaven there.