It's a mixed blessing to work in I.T. On one hand, we can access anything anytime from anywhere. (Trust me - I've handled tech support from 15 time zones away.) On the other hand, the bad news is that we are tempted to use these super powers to cut into our personal lives.
When you're a sole proprietor, this unbalances your life and keeps you working all the time. But when you have employees, the problem grows to affect your entire company. You have to pay for the labor, frequently at after-hours rates. And if you pay on a salary basic, you pay the price in overworked employees who never feel like they're off work.
So there's both an internal component and a client-facing component to your policy. It starts with a commitment to working normal hours. Set hours in the range of 8AM to 5PM or 9AM to 6PM. Or have people work slightly offset shifts and keep it in the range of 7AM-7PM. That gives you a few hours to remote into client machines before and after their work hours.
Externally, you need to set an after-hours rate. For us this has always been twice the normal rate. Some people prefer 1.5x the normal rate. Whatever it is, it should be painful enough so that clients don't easily say yes to paying it.
Most clients aren't trying to make you work longer hours for free. They're just putting in tickets and asking for help. And you'll get zero pushback if you say, "We have to charge extra for after-hours work." It's a very normal business practice.
Here's a video on this topic with additional tips:
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