Required
Be Clear
A dog who doesn't understand what is expected cannot consistently meet expectations. Ensure you are being clear in how you are asking for desired behaviors, or how you are correcting the undesirable.
Be Consistent
You will hear me say it time and time again, consistency is key. Just as you wouldn't expect your single gym session a month to give you long-lasting results, you cannot expect a single training session with your dog to give you long-lasting results.
Make it Fun!
Never train when you are frustrated or upset. You simply will not see results. Should you find yourself getting frustrated mid-training session put your dog away and try again later.
Create Motivation
Training should primarily be about building motivation in the dog to do something rather than them simply avoiding punishment. Creating motivation takes time and patience (and lots of teats, praise, and toys!).
You are Always Either Training or Un-training Your Dog
Keep this in mind always. Every interaction with your dog for their entire life is an opportunity for learning (or unlearning) desired behaviors.
Balanced training is a style of training that incorporates both reinforcement and punishment, essentially we say 'Yes!' and 'No' to clearly and efficiently communicate the dog what we are looking for. This style of training allows us to 'train the dog in front of us', meaning we can utilize all the tools in our toolbelt dependent on how the dog will best succeed.
I want a dog to be motivated to do desirable behavior and it is our job as handlers to motivate the dog and our job to teach him the desirable behavior. Once the dog has an understanding to perform what is expected we can begin to start adding in minor consequences for disobedience. If we have to make many corrections for the same behavior then we can reasonably assume that we have not given the dog enough information about what is expected. In almost every correction I give, I want the message to the dog to say "Don't do that, do this instead". For example, "Don't jump on the couch, go to your bed instead", or "Don't bark along the fence line, come to me instead" or "Don't jump on guests, sit instead" etc..
All corrections should be unemotional. I like to use a tone of voice that sounds like "No, we just aren't going to do that", very matter-of-fact rather than mean or angry. Rewards are celebrations! Your dog did a great job, whether it be going to their bed, not jumping on folks at the door, or came back to you the moment you called them. Ensure this reflects in your tone of voice as well.