It’s worth noting that the TCJA did not change the rules for self-employed persons. If you are self-employed, you can continue to deduct qualifying home office expenses. Typically, you would report the home office deduction on federal form 8829, Expenses for Business Use of Your Home, which is filed along with your Schedule C, Profit or Loss From Your Business, on your personal 1040 (note that each of links is to the 2017 version of the form and will download as a PDF).
For me, I like to keep things simple. I use Google email + calendar, but my clients use Calendly to schedule appointments so we don’t waste ten emails sorting out a meeting time. I use a screencast plugin for Chrome to record any voice-overs for deliverables so I save HOURS on conference calls going through slides. Calls are now about questions and discussion, not deliverable presentation and review. I use Dubsado to track leads and send out contracts, invoices, and automated emails based on dates and specific client actions.