1. To go too cheap or too expensive on computer components. You don't want to be out buying a new computer every year just because you bought a lousy $50 CPU that doesn't fit your gaming needs but you don't want to pay a thousand dollars for an 10 Core CPU or 12 Core CPU if all you do is go on Facebook and play vintage games all day. You want a happy medium between the two but also a budget which brings me to my next bullet point.
2. Don't worry about a budget. If you're some rich guy that has a lot of money in their lives then fine I guess this doesn't really apply but for majority of people here, you'll want to stick with a budget. There should be a limit of the maximum you want to spend, If you have to trade a Solid State Drive to make room for a more expensive graphics card or CPU then do that. We can't just go to an online store, Put stuff in a cart and expect it to pay for itself you know. That money has to come from somewhere.
3. Delete System 32. Now some people have said this as a joke or troll bait for some inexperienced chump to delete their System 32 file under drive C:// (The System's default drive) but I'm sure there's people that have really took that advice and followed through on it. Don't do it because you won't have a working operating system which means you can't browse the internet, log into windows or even play your favorite game.
4. Anybody can work on computers. No, Not anybody can at least not right off the bat. You have to learn how to do this stuff for starters and even then there's still stuff that you learn later on. There's a lot to learn but the basics is what each computer component does and how to best handle the parts themselves without risking damage. The most obvious of these things is if you produce a lot of static electricity then you need to wear a protective wristband to prevent damage to components. I personally don't use one but then again I didn't give off static electricity unless I was at school and that's one thing that benefits me when I do computer work at home.