When shore and wash fishing you find reasonably deep water right up at the rocks and a swell that is causing water to wash over and against them. In this situation fish will often be found further down in the water column where there is less surge.
Here, the fish will be waiting for anything that the swell dislodges from the rocks, quite a feast that can range from fish to crabs and small shellfish.

Placing yourself in a safe position to enable a cast directly into any wash action is best achieved with the utmost care. You don’t want to put yourself in a position where you may be taken into the rocks.
If you fishing from a boat, the best approach is to have one person operating the vessel and leaving the motor running, while the others on-board have a cast.

When shore and wash fishing it is possible to cast and retrieve much like you are doing while on the drift from a watercraft with the only difference being that you are stationary. To compensate for this, it is necessary to cast around in all manner of directions working the soft bait back towards yourself as you go.

Read more about Drift Fishing

Placement of the lure is quite important in this situation and usually the angler with the best placement and most well suited weight of jig head will have the best advantage.
Weights used in this situation can range from one quarter to five eights of an ounce and heavier depending on the size of your soft bait and the depth of water below.
To start with, try casting further out from where the main wash action is hitting the rocks, and from there adjusting the soft bait to get closer in each time you cast. This will give you the opportunity to cover more area as you move along.

A word of caution when casting close in to the rocks: if you let your jig head and soft bait come in contact with any foul ground for too long a period of time, it will most likely become stuck or snagged if left unchecked.