Setting Up the Tor Browser Properly
The Tor Browser is secure by default, but the defaults assume you will tighten a few things. For a darknet market, those few things are the difference between a clean session and one that leaks. Here is the setup, in the order to do it.
Install from the only source
torproject.org, and nothing else. A repackaged installer is a common way a machine is compromised before the first circuit. Verify the signature on the download if you are being careful, and skip the step if you are not, but know which one you chose.
Move to Safest
Shield icon, security level, Safest. Scripting is off, and the market still loads. Leave it there. Moving it up for a page that will not load is how a script gets onto a page you thought was clean.
Circuits and new identities
A new circuit is a fresh path through the relays, and it is the fix for a stalled address. A new identity clears the cookies too, which is what you want between a market and anything else. Do not mix them in one identity. That is the leak.