I’ve never tried charging by the hour, but my intuition is it could lead to micromanagement from clients, and also create stress/overhead for me in accounting for each hour. I also worry it would make clients uncomfortable to know I’m constantly context switching into different projects throughout the day.
What if I spend an hour of the day researching a solution? Does the client need to know the details of all 8 hours of my day? I prefer to keep a “work log” spreadsheet, with a row for each day explaining at a high level what I accomplished, and also keep in daily communication with the client to make sure we are on the same page.
How much information do you give your clients as to what you did each hour? Have you ever tried billing in larger blocks? If so, how did that method differ from charging hourly?
It's the only sane way to do it, and contra to your intuition it stops micromanagement and makes clients respectful of your time. Clients don't know or care about context switching for other clients, they care about the quality of the work provided, so take care of that and you'll be ok. It's not like you'll be constantly switching anyway. Usually I'll work all day or all half a day on one specific thing anyway.
In terms of accounting for each hour, there are software tools to help with that.
Just click when you're working and click when you stop and the software tallies up the time.
I don't provide clients with hourly breakdowns of everything I worked on, I just send a bill at the end of the month that includes total hours worked that month.
Regular video calls and email, plus delivered results are sufficient proof of work.