To prepare the sardines, use a butter knife to carefully scrape off the salt, and the skin of the sardines. Remove any tough parts of the fish. You don't need to remove the bones; these are relatively soft and small and can be eaten. Watch video here. You also don't need to remove all of the skin as some of it will also come of when you are rinsing the sardines.
Prepare the anchovies in the same way that you do the sardines, but be even more careful. These smaller fish are more delicate and scraping too roughly will break them apart.
Once you have cleaned your sardines and anchovies, rinse them under cold running water, one by one. Use your fingers to gently clean them, wash away any remaining salt and rub off any remaining skin. You can certainly leave some skin on .
Place your sardines and anchovies together in a shallow dish (or keep them separate if desired) and pour the red wine vinegar over the fish to almost entirely cover. You may need a bit more than the listed amount to do so.
Allow your fish to soak in the red wine vinegar for 5 - 10 minutes. Then, pour off the vinegar and cover with olive oil.
Your sardines and anchovies are now ready to serve.