I spent roughly 13 hours watching countless YouTube videos about how to brew the perfect pot of coffee on a Chemex. The good news is that I have found the best video (below) that you should find helpful, the bad news is that everyone does it differently so you will need to experiment and find the best process for you.
Here is my commentary on how to brew with a Chemex as well as a few videos that should be helpful.
When I was trying to make a decent pot of coffee, none of the videos I found talked that much about the grind of the coffee, but I knew that is where I was having most of my troubles. The number one thing to keep in mind for your grind is consistency. You can make tweaks to the actual coarseness, but if you don't have a consistent grind, nothing else matters.
If you have a low quality burr grinder, this can be difficult and if you have a blade grinder, it's tough as well. I don't know a trick for fixing a bad burr grinder, but if you are using a blade grinder, grind in short bursts. It's really annoying to do so many bursts [ especially if you are trying not to wake up your 1 year old son :) ], but trust me, it creates as consistent of grind as you can get on a blade grinder.
"I'm not going to measure the water. I don't care what the videos say!"
"I'm not gonna do it! It's close enough, plus what does a few ounces difference matter?"
These are all comments that I made at one point of another. After saying that and then finally caving and measuring the beans and the water, I now know why all the videos instruct you to do so. It's worth it. Do it.
Brewing on a Chemex is like any other skill, the more you do it the better you get. That being said, you want to control as many variables as possible so you can master the speed, rhythm, temperature, etc. of everything else involved in this process. I don't measure the temperature of the water, but I do bring it to a boil and take it off the heat for 20-30 seconds before I wet the filter and pour the water over the beans.
Don't skimp on the blooming process. After the water first comes in contact with the beans, the beans want to release gases. Giving the coffee time to bloom allows the beans to breathe and release those gasses before moving on to the full brew.
I visited a badass coffee shop in Columbus, Ohio called Mission Coffee Co. and chatted briefly with the barista about how to best brew on a Chemex and the main pointer he gave me was to stay away from pouring down the side of the filter. By pouring on the sides, (I think) you are moving some of the grind that naturally want to stick to the filter and clogging up the bottom of the filter. This can lead to slow brew times and over extraction.
He didn't explain all this to me, this is what I have gathered, but nevertheless, try not to pour on the sides as you are brewing. Also, be sure to have a nice kettle that pours from the bottom with a curved spout. This allows you to highly control the speed and location of the water as it is coming out.
The best video I have found about brewing on a Chemex is from a barista at Intelligentsia. If you have other videos that you suggest, please share them below in the comments.