I'll be leaving town for about a week shortly. This is a tremendous challenge for a solo practitioner.
You have to get all the work on your desk done, so when you get back you can deal with all the stuff that came in while you were gone.
You have to get someone you trust to read your mail, and tell you if anything comes in that requires attention before you get back (or right when you get back).
You have to arrange for others to cover for you on things that come up while you're gone. And you generally have to pay them to do that.
You have to accept that you will lose revenue while you're gone. Some clients will not hire you if you're not going to be there.
Perhaps worst of all, you have to deal with things beyond what I describe above, that you didn't anticipate, and you have to make decisions on the fly.
And somewhere in there you have to enjoy the vacation. :-)