heres a copy of a report in the forum on directions if you stuck next time m8 try the search at top of page... hope this helps tite lines... aka clive.
the best way to the Ranny is to drive through Penarth down Redlands road which leads into lavernock road. then just after Cosmeston Park (which is on your right) take a left down to lavernock point (which is sign posted). Park by the small church at the end of the lane and take the path to the beach. Then walk about 500 yds to your left and you'll be fishing the ranny.
The knap as far as i know is fishing best from high tide down as much as 4 hours, mainly whiting and pout have been caught, the only cod i've heard of was at cold knap point on low water.
Baits to use are worm and fish bait cocktails!