Just as in a burn of the furnace, for example, it is important to cool down the skin. The sea or the swimming pool are excellent solutions. Keep a good few minutes in the cold (lukewarm) water. Do not take a cold shower, because the temperature distance is too big. Was not your skin while showering with soap. This dries out the skin and thus ensures that the skin is painful. Repeat this daily. You also can take a wet towel for on the places where you're burned.
Keep your skin as fat as possible. Not only if the skin is burned, but all the time when the skin has been in the sun. The sun dries out the skin, so proper care to recover your skin is never to much. You can use aftersun. It is important that it has an emollient, moisturizing cream or lotion.
Burned skin should not exposed to the sun. So stay in the shade and cover your skin if you want to have a walk! Cover the places were you are burned and if you still want to go for a walk just take a hat or scarf with you.
Can you not wear your bra because you really burnt your shoulders that it hurts that much, wear a strapless bra or a bikini who is nice. It is now just to keep your skin nice and that you feel good.