Love my Plaice fishing. It's still a bit early because of the rotten cold spring but they are slowly starting to show. Key thing is weather conditions - you need a calm, settled period and preferably a nice calm sunny day. Any kind of colour in the water and you can forget it although interestingly I have had two of my best three Plaice after dark. Plenty of marks to try - Hendon Prom, Shields Pier, Marsden, Middens to name a few.
Some swear by Wishbone rigs but I've had most of my Plaice on two hook clipdown rigs, 1/0 hooks and don't skimp on the ragworm - Plaice are greedy buggers. Tip off with a small sliver of squid or Mackerel. Not a fan of bling myself but it doesn't hurt either. Leave the bites to develop and they will hook themselves...
Good luck, I'll be out Sunday morning tide hoping for my first of the season