<li>Transmission can watch a certain folder (eg your Safari download folder) for torrent files and then open them automatically via Preferences → Transfers → General.</li>
<li>By default, Transmission deletes the original torrent file upon opening. If you remove a transfer, in order to resume it you will need to reopen the original torrent file in Transmission. Simply choose 'Save Torrent File As…' from the File menu before deletion to avoid having to download the torrent file again.</li>
<li>Once your download is complete, you can set a default ratio to automatically seed to, and then pause. This can be adjusted in Preferences → Transfers → Management, or in real time using the Action menu.</li>