First of all, trying to change the boss's mind and let him know the implementation degree of a complete set of rules and regulations plays an important role in the healthy development of enterprises. Of course, old employees should respect, but they should consciously abide by the enterprise system. If the boss is very supportive of your reform, then you may continue. If you don't even want to change your boss, or are too lazy to change, I think you'd better forget it.
2. How to deal with the relationship with old employees? You are the superior of these old employees? Level? Or subordinates? Then you have to make changes according to your relationship. If it is your superior, then you should try your best to maintain their dignity and respect their status. Is it an old man after all? It's not easy to be where you are today. Don't let him feel threatened by you. If you threaten him, don't talk about reform, and your job will be lost.
If you are a colleague, then you should communicate with them more, preferably in other occasions, such as KTV, wine table and so on. It is best not to be in the workplace. It would be great to do what he likes. Don't ask for anything in return, just ask for their support.
If you are a subordinate, you should also respect the ideas of the elderly. If they don't cooperate, you will not only fail in reform, but also lose your reputation.
In your daily management, treat everyone equally, and don't let the following people say that your management is unfair. Be strict with yourself and set an example for your people.
That's a little too much. From experience, don't take it personally if you don't speak well. Please add points if you are satisfied.