There are lots of long blogs about how to do this. Some are written for the beta version of High Sierra and are wrong. Here's the quick and dirty on trashing your APFS disk in High Sierra and go back to HFS. 

Why?
APFS is brand new disk partition type that Apple introduced in High Sierra. Although it has some benefits, I don't care for it. Anything that apple releases that is brand new, be weary, there are usually issues with it. Also, if you're a mac tech reading this, upgrading OSes or converting from HFS to APFS to solve performance problems is not a solution. If you need help understanding why, email me. 

***WARNING: THIS WILL DELETE THE CONTENTS OF YOUR HARD DRIVE. MAKE A BACKUP***

FIX:

• boot into the recovery partition by holding command-R during boot.
• click utilities in the top menu. 
• select terminal.
• type and hit enter: diskutil list
• you'll see the list of all the drives. look for "APFS" then the disk identifier to the right, something like "disk0"
• type then hit enter: diskutil apfs deleteContainer disk-identifier-here

That's it. You can now re-install, re-store, re-image to your HFS disk however you like. You're welcome. 

if you've goofed around and tried to change your user name though the advanced settings in your mac, you may have ended up with your user switching back to a standard account. if you only started with one account, then you've left yourself with no admin account. Aaaand you can't change anything. Here's is what you do:

• reboot your mac
• hold command-S before you hear the chime
• you'll see a bunch of verbose text fly past. when it's done...
• enter: mount -uw /
  
• hit return
  
• enter:  rm /var/db/.AppleSetupDone
• hit return
• hit control-D on the keyboard to restart.

Your mac will now boot and start the setup wizard again. Go ahead and create a new admin user. 

​You're welcome. 

crashplan backup for mac has always been a poor performer with bloated options. now they have discontinued the "home" cloud backup service and move to a totally business platform. It's still a crummy service in my opinion. Uninstall it with this little app. a few clicks and it's gone. You're welcome. 

Here's a quick one. 

The Situation: you have a million screenshots on your desktop. You curse mess and want to take control. Great! Set a folder to keep all the screenshots automatically, rather than turning your desktop into unwieldy monster.

The Fix: 

• make a folder on your mac where you want to save your screenshots. Name it whatever you want. 
• open the terminal.
• paste in this command: defaults write com.apple.screencapture location
• don't hit enter yet. after the the word "location" enter a space then drag and drop the new folder you created for the screenshots into the terminal window. That will auto fill the path to the folder, and should look something like this (if the folder is on the desktop titled "Screenshots"): 

defaults write com.apple.screencapture location /Users/yourusername/Desktop/Screenshots​

• now hit enter!
• next, enter this command and hit enter to reset the system to activate it: killall SystemUIServer

That's it! Now when you take a screenshot it will be saved to the folder you created rather than the desktop. You've tamed the beast. Pat yourself on the back. You're welcome. 

The MacOS setup assistant will only run once. If you've created a user and you're unhappy with it, or you want to migrate another user over you might want to reset the OS so the SetupAssistant runs again on next boot. The setup assistant differs from the Migration Assistant by allowing you to choose a specific restore point from a time machine, rather than just the last backup. This is great if you need to go back to a stable OS before you had problems. Here's how:

• Launch Terminal from the Utilities folder
• copy in: sudo rm /var/db/.AppleSetupDone
• Enter your password.
  
• Restart your mac.
  

On next reboot the system will start the Setup Assistant again. You're welcome. 

I'll keep this short and sweet. Malwarebytes has for many years been the go to tool for Mac users to easily find and remove malware from you Mac, FOR FREE. Recently they released version 3.0 which is now a subscription based model and only runs in a trial mode. They clearly went the route of building a user base with a free tool then switched it on us. 

Welp, here's the last FREE version of Malwarebytes for Mac that will remove malware for FREE! Of course, don't accept the upgrade if prompted to do so. Enjoy. You're welcome. 

This is going to be a quick fix. I've encountered a few clients that have a rare problem where they try to log into their iCloud (via system preferences) or log into the App Store and they are greeted with an error stating "This action cannot be completed. Try again." 

You have bad system permissions. Why? Looks like it's associated with an OS update. 

Fix:
Open terminal and paste in each line separately (3 lines), hit enter after each one, then enter your password. Line two and three wont prompt for your password after you've entered it into the first line. 

1. sudo mkdir -p /Users/Shared
2. sudo chown root:wheel /Users/Shared
3. sudo chmod -R 1777 /Users/Shared

Restart your mac. iCloud and App Store will work. You're welcome. 

I've run into some problems with Apple Photos, the new photo app that replaced iPhoto. I had a need to run an older version of iPhoto on my MacOS system. This copy is downloaded directly from the App Store. ENJOY.

Update 10/9/18 - verified to run on Sierra 10.12 and High Sierra 10.13.