Whether it’s for Boxing, Kickboxing or MMA sparring should be one of the most important and enjoyable aspects of training. Unfortunately it is also easily the most incorrectly applied. Learning how to spar should not be a survival of the fittest situation. Ideally, learning how to spar should be fun, safe and accessible to anyone willing to put in the work. 
In this article I cover some general concepts to apply to your training and then the exact progression I use to take anyone from zero sparring experience all the way to full Performance Sparring rounds. 
Do Not Mistake Training For Competing Or Competing For Fighting.
The purpose of training is to improve.
The purpose of competition is to win.
The purpose of fighting is to survive or protect.
Sparring is a part of training therefore the primary purpose of sparring is to improve your own and your training partner’s skills. You should be able to move and act deliberately – If you are going so hard that you can’t think, then you can’t learn. 
Over time the intensity at which you can train while remaining deliberate will increase. What is a high level of intensity for you today should become a low level in the future.
80% Speed And 20% Power.
Sparring with heavy levels of contact – or “hard sparring” – is often equated as being superior to sparring in a more controlled fashion. Nothing could be further from the truth. When you spar with moderate or light levels of contact you are able register your mistakes without being unduly punished for them. This enables you to spar more creatively, take risks you might otherwise shy away from and work on parts of your game that would otherwise take years to develop. It also allows you to spar more often as the recovery between sessions takes significantly less time. 
It is important to note that I am not advocating non contact sparring. There is a world of difference between practicing striking your training partner with control and practicing missing your training partner. 
So while regular hard sparring is terrible for developing your skills and, more importantly, your health you don’t want the first time you get hit hard to be during a bout or in a self defence situation. This is where acclimatisation drills come in. Specific acclimatisation drills are an excellent method of introducing high levels of force to your training. These drills are significantly safer than participating in hard sparring matches and allow athletes to progress at their own level. They come in many forms but the most common is to have two athletes perform tennis match style sparring (see below) with a set combination of punches that the receiving athlete defends and can then ask their partner to deliver next combo with more, less or the same amount of force. 
Performance Sparring vs Sparring For Development. 
In a Performance Sparring session you are practicing using all of your techniques, tactics and strategies to put in the best performance possible. When sparring for development you are practicing a specific technique, tactic or strategy in order to further develop that skill. 
Both types of training are very important to perform regularly. Generally speaking, an athlete should spend about 75% of their sparring time sparring for development and 25% sparring for performance. If they are preparing for a bout this should gradually move towards a 75% emphasis on performance sparring over the course of the fight camp
Most important of all is to come into every round with a clear purpose in mind and then hold yourself accountable to that intent. 
learn how to spar
Work At Your Partner’s Level.
Working at your partner’s level is an excellent way of ensuring your sparring match is a positive training experience for both you and your training partner. As previously stated, training is not about winning but about improving so if you can learn to spar in such a way that you can improve regardless of the skill or athleticism of you partner you will have found the key to life long learning.
When training with someone with more experience than you attack as skilfully as you can and prepare to work on your defence.
When training with someone with less experience than you attempt your least developed techniques. Allow your partner to attack and endeavour to counter.
When training with someone who has similar experience to you spar as best you can focusing on proper body mechanics, techniques and strategies.
Listen To Your Coach.
Learning to act on the instructions your coach or your corner is giving you is something that takes time and practice. You can start by trying to keep in mind the directions and advice your coach and senior training partners have given you. Watch and study them as much as possible when trying to improve and advance. Take advantage of their experience. Where you are, they have been.
Give Your Training Partner Everything.
Give your best effort to your partner throughout the entire sparring match. As mentioned previously, this doesn’t mean you should go as hard as you can but instead means you should be putting forward genuine and sincere effort for the entire round. Whether there are three minutes or three seconds remaining in the round you should be working and you should never give up a match half way through because you are disheartened or tired.
Shoulder Sparring 
This is almost like playing a one on one game of tag. The goal is to tag your opponent on the front or side of their shoulders without getting tagged in return. Both athletes must maintain a good fighting stance throughout except that their arms should hang loosely down by their waist. Athletes defend themselves purely through footwork or body movement – no catching or deflecting with their arms.
Tennis Match Sparring
In a game of tennis two players take turns hitting a ball back and forth and tennis match sparring works much the same way. In this sparring game two athletes go strike for strike or combo for combo, back and forth through out the round and it’s not permitted to attack while it is your training partner’s turn. Emphasise movement, angles and proper distancing throughout. 
Tennis Match Sparring With Counters
This is identical to the previous stage of progression except that during your opponent’s turn to attack you may attempt a single counter strike. 
Limited Sparring 
Both athletes can attack at any time but either the  type of strikes or the available targets are restricted. For example you might run with jabs only or body shots only. The possibilities for this stage of progression is pretty much limited only by your imagination.  
Open Sparring 
All strikes and strategies permitted. 

While this is by no means a comprehensive list it does include each of the major milestones that an athlete must progress through in order to be a safe and skilful sparring partner.