Best way to keep fermentation temperature with new freezer and Johnson controller?

So I just purchased a Johnson controller and a used freezer to use as a fermentation chamber. My question is about how to properly use the Johnson controller with the freezer.

Should I leave the probe in the open air in the freezer? Put it directly into the wort? Put it in a separate container of liquid?

I've heard a lot of different opinions and am curious as to what HBT thinks is the best way to use this equipment.

What are you fermenting in? I'm of the opinion that the probe should be reading the actual temperature of the beer. They make carboy bungs with thermowells that you can use. I tape my probe to the side of my carboys then tape a form of insulation over that. It's quick and dirty and gets the job done.

I am fermenting in a bucket.

You can drill and gromet your bucket lids for a thermowell or you can tape the temp sensor to the side of the bucket then tape some sort of insulation over the top of it.

^ That right there nailed the two best options.

Cheers!

If you tape the probe to the side of the carboy or place it in wort, just remember the freezer will start cooling and will not cycle off until the wort is at the right temp. This causes the temp in the freezer to become much colder (becasue of the lag) than it needs and may end up cooling the wort down further than you want initially.

Since the act of fermentation usually increases the temperature around 5 degrees (plus or minus) in a 5 or 6 gallon batch, I place my probe inside the freezer (measuring the air temp), and usually set my controller at about 5 degrees lower than my target fermentation temp. This gets me within a few degrees of my target temperature. After a few days I decrease that to around 3 degrees. I use a laser temperature gun to monitor the wort temp.