1. You can now start scanning the image. The best way to scan it is to import it directly into Photoshop so it can be immediately saved as a psd file. Here's how to do it: While in Photoshop, select File, > Import, > (Select your scanner). The keyboard shortcut is: Alt+"F", "M", (Highlight scanner), Enter.
2. The choice is entirely up to you wether you'd want it scanned as a large file or a small one by selecting the desired dpi. (dots per inch). My usual method is to scan a large file and shrink it to a disk-space friendly size. For example, I'd scan the pic for 300 dpi., and I resize it to 150 dpi. (50% size reduction). The details are more preserved than if you originally scanned it at 150 dpi. image.
Here's how you resize an image: Image, > Image Size. The keyboard shortcut is: Alt+"I", "I".
3. "My drawing came from a book/notepad, so I had to scan it upside down, sideways, etc."
Don't tear the drawings off your book or pad yet if you don't feel like it. You can scan it in any position you'd like. The same goes if you're scanning an image as large as A1 sized and couldn't help scanning it upside down, etc.
To reposition the drawing the way you'd like, select: Image, > Rotate Canvas, > 180, OR 90 CW, OR 90 CCW, OR Arbitary. The keyboard shortcuts are: Alt+"I", "E", 1, OR 9, OR 0, OR "A".
The arbitary command allows you to rotate the image manually by selecting the rotation degree.
