You have to be careful with your typing
In practice this is not an easy thing to advise on. Many Linux installations go very smoothly, others have strange problems. I do have some general recommendations though:
1.
Keep a "System Admin's Notebook" and really use it. Although modern Linux installations auto-probe and lead you by the hand for a long way, there comes a time where you need to configure things yourself. Note down everything that you do, including any software you load, any file/files/configs you edit, what you change from and to, how you locate the file/menu/dialog, where you look up what to change and why you did it. Thinking to yourself "Oh! that didn't work, how do I change it back" or "I know I did something like that last week, but what was it I changed?" are prime sources of frustration and wasted time.
2.
Don't be afraid to reformat and start again. It's unlikely that you will have any irreplaceable content for some time (and it should be backed up anyway!), so the only work you lose if you reformat is the effort you have spent loading and configuring software. This should all be in your notebook, and if you have it written down
you should be able to avoid blind-alleys and get the system up much more quickly next time.
3.
Know your hardware. This is getting a bit less important than it used to be, but you will need it if you plan to use plug-and-play hardware. Check all your hardware (don't just guess or believe the driver information) and note down everything you can including IRQ, DMA and memory usage, the full manufacturer and product codes, and the numbers of the main chips on the boards. Getting (for example) sound
cards and network adapters can be a breeze if you have this information or a pain if you don't. Know how much memory and hard disk space you have, and how much space on which disk you want to allocate for Linux.
And finally...
4.
Don't Panic. It's much easier to stay calm if you are prepared, so: Backup everything first if you are adding Linux to an existing system. Read the installation manual, don't just skim it. Give yourself plenty of time, don't rush.
Let us know how you get on.