Ronsomna, it depends on how much time you have, or how much you are prepared to put in? "The Knab" at Mumbles is a very comfortable spot where you can virtually fish out of your car, but it aint that much as you would expext!
The "Mumbles Lighthouse Island" is your best e/w bet, the causeway opens 2.5hrs before LOW WATER & closes 2.5hrs after LOW WATER. Fish INTO Swansea Bay from the ruins of the old landing stage, casting at the Port Talbot Steelworks. If possible use peeler crab (gather it on your way out or buy it) or mackerel fillet, or large frozen sandeel.
Keep your eyes on the flooding tide on the causeway! if you get caught out on the Lighthouse Island by the tide, STAY THERE! wait until it runs out, DO NOT ATTEMPT TO CROSS THE FLOODED CAUSEWAY! Spinning on HW in the sound between the Lighthouse Island & Middle Island can produce bass, Pollack, mackerel & gars.
But for Christ Sake be careful, the flooding tide rushes in! Unlike England, in Swansea next week we have a 38ft rise & fall in th etide!!!!!!!!!!!!!!!!!
You can also try Langland Point 3hrs either side of high water, either bottom fish (inside the head into the Bay), or spin the rocky area directly off the point. If you want any help whilst you are down here send me a pm .
blueskip