^ +1, theres no rush, take your time
Just going through the steps repeatedly will force you to familiarize yourself with the process. After doing it a dozen times, it'l become 2nd nature, as nearly all scopes are the same (in how they operate)
The boresighter is a basic tool, and unless you're shelling out $100+ for a premium unit, its only going to get you so far in the process of sighting in. It's going to get you on paper, and that helps. From there its all fine tuning to meet your needs.
Make sure you're using the correct size dowell/attachment peice (that matches the exact diameter of your barrel). Anything smaller wont give you the tight dimensions you need, and as a result, throw the boresighter off.
Slide the unit down the barrel, as far as possible or as you feel comfortable doing. Place the rifle in a good, sturdy rest so you can start making adjustments, then turn it on.
Example. You fire 3 shots. Your grouping places 2 inches below and 3 inches to the right of where you were aiming. (assuming your scope uses 1/4" adjustments). So you would go 'Up' 8 clicks, and 'Right' 12 clicks.
In theory, this should put you around where you were aiming. Fire Another 2-3 to confirm, then adjust again, as needed.
Other than that, dont try to adjust after each shot, shoot a group of three to determine where the average placement is, then adjust. Repeat if needed. If you're a good enough shot, you could probably get it done in 3 shots
It all depends upon your intended purpose for the rifle/pistol, but this should get you where you need to be