Taking time out - do you still turn on your out of office?

I would talk to all of your regular clients before you go and get everything wrapped up. I would make mention that you'll be away so your deadlines will be met before you go or once you return (if possible, perhaps there are some things that you could push back by a couple of weeks so you know you've got a few tasks to come back to).

For any new business, I'd definitely put an out of office on your email explaining that you're away from your desk until such a date, you have access to your emails and will be checking intermittently and you will respond to them personally when you return. This way, your potential clients won't think you've dropped off the face of the planet and take their business to your competitor.

There's no need to explain that you're on holiday and not doing a scrap of work, but it's good to have something communicated so it doesn't make you look unprofessional or slow to respond.

Perhaps allocate a ten-minute window each day where you run your eye over your inbox to see if there's anything pressing. You could also ask a friend or family member to be a point of contact in your absence and add their email address to your out of office so that if anything urgent that comes up you'll have someone to communicate with your client and you won't have to be bothered at all.

You're right, it's so important to take breaks but as small business owners, it is extremely difficult to switch off completely. Life goes on though, so whatever you decide, the consequences of switching off completely will only be short lived.

Enjoy

However you approach it -- you are wise to take time out. It's an investment!