Here is a guide to hitting others. It is not about safe impact locations or how to develop picturesque bruising. It is about how to hit someone, and keep hitting someone, until you're both satisfied. It is how I approach hitting masochists for my own pleasure.
The first thing to note is that...
That fact cannot be shied away from. Pain, even for masochists, hurts. There is a tolerance to how much someone can take, and ways to engage with that tolerance. You will need to learn how each masochist takes pain, and potentially even teach them how to manage and endure it.
So you've got a paddle and a tied up piece of masochistic meat, or perhaps you're using your hand and it's bent over your knee, or perhaps it's cuffed to a cross and you've got a whip, or perhaps you've got a knife or needles or... well by now I've laboured the point enough.
How do you get the most out of your meat?
Start slow. Hit them slowly and rhythmically, building up in intensity every few hits, and when they tense too much or start struggling to breathe or can't stop themselves from making too much noise, slow down again.
Your aim is to warm up the meat so that it can get used to the pain, and once it's used to the pain you can intensify it. Climb up, drop down, and climb back up again. Vary the strike location, but remember that locations you haven't hit as much will need warming up too. The more skilfully it's done, the more you'll get to hit it.
On the subject of their breathing, tension, and noises, you'll want to pay attention to these as you hit them. As you hit them, their breathing will try to get sharp and shallow. Their muscles will try to contract to harden against the impact, and they'll make noises as reactions to your hits. Encourage them to keep their breathing steady and calm, and they'll take the hits better. Encourage them to relax so that the impact dissipates into their flesh instead of getting caught in their tension and you can hit them harder while hurting them less. Listen for moans of pleasure if they're so inclined, and encourage them to verbalise their pain, intentionally responding to pain verbally will help them endure it. Let them calm themselves between your hits, and they'll feel like they can take it and let you push them harder.
Watch how they react, but be aware that you may need to soothe or goad them. Try different things: Hold your off-hand on their shoulder so that they can brace against you. Praise them for each hit you've delivered. Tell them they can take more for you. Tease them. Rub them while they catch their breath and tell them how happy you are with them for taking it. Be verbal, but don't expect responses unless they enjoy responding. Pay attention to what helps them calm.
Once you've got the hang of these things, you can begin to play with them and challenge them: forbid them from making noise. Blindfold them so that they can't prepare for the pain. Make them watch you hit them so that they can't help but tense up in response, and play with false swings to mess with their minds. You can be cruel, because you know how it works. You know which moving parts can be shifted, and which must stay still.
Consider also what your masochist wants from being hit: some do not want to be overwhelmed, they want to be guided and hit into a meditative place where they can dissolve into the pain: intense but never too much, and then you can hit them until they're bloody and raw. Others want their pain to push right up to the edge of too much and stay there until they break. They want to cry and scream, and your challenge is to see how cathartic you can make it: break them too quickly and they might not find it satisfying, and neither will you.
And afterwards, aftercare, and you can work out what that looks like with your masochist yourselves.
