Not having the phone with you is critical. But I assume planning is done on a laptop or desktop that is obviously not taken with?
Yep, anonymous browsers, burner accounts, and a VPN if you can. Privacy.sexy is your friend too.
You just want to set yourself up as best you can for the defense of “you can’t prove that was me.”
Tor browser/ I use a VPN most of the time. But for REALLY sensitive shit I turn Tor on. A lot of stuff can be purged off your computer. I use Windows 11 (haven’t migrated to Linux yet! Ugh!) but I have some failsafes to reduce my location data and the amount I am exposed. It isn’t perfect (nothing is) but it is better than nothing.