Yeah, easy to happen. In the end you are the one responsible for properly maintaining your bike/car.

I love suspension. It's so complicated and interesting.

Free sag, rider sag and rebound is something every rider can measure himself best with a friend. Compression is something you can't measure you need to ride the bike in order to set the comp but that is more preference than anything else. There is no right or wrong in comp. Air gap, oil viscosity... is something that is written in either the workshop manual or the install instructions from the hardware you bought. In case of Öhlins it can be downloaded from the website. If you don't install suspension components yourself, air gab and viscosity are too things you don't need to worry about. It's not rocket science to set up the suspension of the bike and some try to make magic out of it when it's really not. In most manuals the standard settings are explained and you can set it yourself and most of the time, those settings are good for street riding. Of course, when you are an obese American those settings will mostly max out and you need to upgrade to stiffer springs or higher viscosity suspension oil if you do it yourself (the suspension).

Yes, I’ll actually be doing a video on that soon!