I would suggest the following:
If you will be spanked over clothes, every layer of clothing between you and the implement used on you will help. Balance the need for protection against the risk of being caught with padding. You can probably get away with an extra pair of underwear. Even better would be a chamois cloth. (It goes without saying that you should take care to make sure your chamois is completely concealed and won’t shift around.) Heavy denim jeans with patch pockets over the seat are always a good choice. Back in the day, heavy jeans were the classic wardrobe choice of kids who faced a school paddling. It is unfortunate for me that all my spankings are on bare bottom.
If you have the opportunity, warm your skin beforehand. A warm bath or shower will do. Make sure you dry the skin well, though. If you forget to dry your bottom I wish you good luck.
Try to control your breathing. Take deep, steady breaths. It works for a while only.
Try to stay calm and relaxed. The fear of pain makes the perception of pain worse. Clenching muscles might help you deal with the immediate sting but can cause more soreness afterwards. Choose if you want the before or after the level of pain.
Try to distract yourself. You might try reciting the multiplication tables in your mind or conjugating verbs. You might focus intently on some object in the room, such as a painting or the pattern of the carpet. The more you occupy your mind, the less you’ll be focused on the pain. For me it hard to focus on anything except the pain,
Find something to hold onto tightly with your hands. Yes, I do grap anything with my hands.
Allow yourself to vocalize. Don’t attempt to hold back your grunts, groans, ouches, etc. Agree I cried and yell a lot.
You might try applying a burn gel with lidocaine. I don’t how much this would help if applied beforehand, but it’s a topical anesthetic. It would probably be very useful afterwards. Make sure to follow the product directions. Also, if you apply beforehand, make sure you do not leave your bottom damp. Dampness might actually cause worse stinging. Good advice of applying lidocaine the problem is my husband do not allow it as he wants the spanking to sink in. Very good advice of not leaving your bottom damp it extra painful when spanked.
What are your suggestions to make it less painful?