James,
If you're new to sea fishing I'd recommend fishing from some rocks preferably with a safe platform to stand on. Put all tackle/clothes etc you're not using higher up the rocks behind you and that way if a rogue wave comes in it won't swamp your kit or worse still wash it away off the rocks.
Float fishing and spinning with a small spinner are your best bet this time of year. The summer species such as mackerel, pollock, garfish and bass are all about now and float fishing or spinning will catch all these species and they are all edible.
If you float fish use light tackle and line it's much more fun fighting a fish on light tackle and the trace and bait will look more natural in the water than if you're using 30lb line. Use about 8lb line on your reel.
It's about hedging your bets, and the best bait to catch mackerel, pollock and gars is a thin strip of mackerel (belly flesh peferably as it's white and is more attractive to the fish as it resembles the small fry they're looking for.) or a thin strip of squid flesh. Cut into an elongated triangular shape no more than a centimetre in width tapering to a point and about an inch long. If you're not catching change the depth of the float. Gars especially feed near the surface so go about 4ft deep to start with.
Thread the tackle for a float in the following order. Stop knot (or simply tie on a rubber band.) This sets the depth of the float. bead, float, bead, weight, swivel (2way) 18inches of trace line, hook. (small aberdeen pattern is best). Hook the bait strip once only at the wide end of the strip. Cast in different places and change the depth of the float if you're not catching, simply slide the rubber band up the line a little higher to get extra depth.
Spinning, use a dexter wedge, small Yann spinner, Nordic herring, or Viva parade. All the mentioned fish will take these spinners, and they all cast well. Try Veals. They'll have everything you'll need and will give you advice if you call them. Excellent company. (no connection etc just a very satisfied customer)
The chaps you saw were probably beach casting from the beach which is a whole different kettle of........................erm............fish
and requires more substantial tackle, rods and reels
That's my advice and if you need to know anything just ask.
Wrasse can alo be caught close in from the rocks but arn't great eating and you'll need rag worm to catch them. Great sport but not so great if you're after a meal. Pouting are also easy to catch from the rocks but again rag worms are the best bait. They deteriorate very quickly so cook asap. With all the fish keep them under a damp towel if it's a hot day (fat chance this year
uppy_dog )
Tight lines.