Better Otto Mechanics.
(Tips to save you the trouble of finding out the hard way.)

• Learn Action Quirks.
Not all actions work as predicted. This list of Action Quirks will take the frustration out of Automator.

• Use AppleScriptlets.
You can extend the power of Automator with the Run Applescript action and AppleScriptlets.

• Clear the cache.
If Automator gets sluggish: Apple-S to save your work. Apple-Q to quit. Hold down the Option key when you restart Automator to delete the cache. iTunes actions are notorious for gumming up Automator.

• Delete Prefs.
Many Automator workflows and apps create their own preferences file. Deleting them can sometimes be helpful if you modify a workflow and it stops working. You'll find them on your system here: HD/Library/Preferences. They're titled "automator.YourAppName.plist".

• Avoid FileType Mismatch.
Automator can convert between some filetypes to bridge one action to another. Check for red type on the right side of the actions. This means Automator can't convert and your workflow will most likely not work as written. Red type on the first action in a workflow is usually fine if you plan on saving your workflow as an app or plugin.

• Use TextEdit for scripts.
If you plan on sharing your workflows, it's best to do as much text work as you can with TextEdit. Other apps like BBEdit and JEditX offer more built-in Automator actions, but TextEdit is already on every system and is free. You can extend TextEdit's abilities with AppleScriptlets.

• Quit Automator.
Exit Automator if workflows saved as applications and plugins are behaving badly. It's not required to run these. Otto tends to meddle in his offspring's lives.

• Add delays.
Many times an Automator workflows calls actions and functions that take time to complete. Sometimes Automator doesn't know that one process hasn't been completed and is on to the next one. The Pause action from the Automator Library allows you to set a delay so a process can complete. Likewise "Delay ?" (?=seconds) in AppleScriptlets will do the same. All machines don't run at the same speed, so if you intend to pass your workflow on to others, err with a delay that's too long as opposed to one that's too short.

• Put Apps in App folder. This is where Automator looks for additional actions that are built into apps. If the app is not in your standard Applications folder in the root of your hard drive, the actions may not show up in Automator.

• Run it again. For whatever reason, Automator has a habit of of not liking a workflow the first time you run it. Probably has something to do with the preferences file that certain workflows create. Always try urring a workflow twice before you assume it needs more tinkering.