Its very easy to do what your questioning... however you sound likea totall noob.
So You must first make note, that: each step of the proccess is just as important as the last.... So if Its /scanned properly /edited-touched up properly /and printed properly.... you will probably end up with more then good enough resaults for an average home user. (that is assuming the IMage your scanning is Good enough quality to start with).
This is not my job or a hobby... But heres a few basic things i do for the task your questioning...
- make shur your picture and scanner bed is Clean of dust, etc.
- IF you wont Max Image Quality, Scan Only 1 image at a time(even if more can fit on the bed).. Its just like any other Image output format on a computer, The more precise the colors are consentrated for the image being output the higher quality it will be.
- Scan the image at 300dpi, fix any brightness/contrast settings with the scanner if Need be, and re-scan.
- tweak/fix any Further brightness/contrast using Photoshop if need be. in photoshop's control tabs /layer/new adjustment layer/Levers /or Cures. By turning both the |Black and |White sliders Down just a Tad on the /Levels Layer, you can restor a bit of vibrance without screwing colors.
and by adjusting the Curves Grid on the /Curves layer, you can fix any Contrast (example- slight inconsitences like Mild Grey dots in White space will Disapear).
- Best to scan the Image perfectly Square rather then Rotate the Image in Photoshop... because any of that kind of image rendering will further Degrade the Image quality. But If you wont to know how For MISC usage, just: Zoom in to the image Realy far... select the (measure) tool, put one point of the measure tool on one corner of the image and the other point on the oposite... then go to /image/rotate canvas/arbitrarry
- The higher the DPI that you can scan the Image the better. IF your scanner cant do ~300dpi or more, at a minimum for good resaults mybe try ~200 dpi. Of course for best quality you would need a decent DPI spec for both your SCANNER and PRINTER.
But if one is worse then the other, this is the best you can do: If the printer has a lower DPI spec, Scan the Image at high resolution DPI and Resize the Image smaller in Photoshop. Just find the max DPI of the Printer(max Output Resolution Divided by Max Output Size(Inches) = DPI), then in photoshop just go to /image/size,and input the proper DPI(res- Pixel per Inch setting).
If your Scanner is Crappyer then your printer... you may have poor image ouput if its scanned at Lower DPI and printed at higher DPI... But IF you wont you can still print at the Native Scanned Resolution witch should give you a good Clear Image(to a degree of course), however printing at the native Lower DPI of the scanner will print a Smaller Image... To do so, in photoshop, go to /image/size... and heres just for Example: If you have image(6"x 4") scanned at 100dpi, it will be 600pixels wide. in /image/size, change width from 600-> to 300 pixels, then change Resolution(pixel per inch/ AKA DPI) to ->200... and you will notice your Pixes will go back to Native 600pix, but Image size will now say =3" instead of 6. but the Image printed should be as clear as possible for a 200dpi printer just for example.
that was just an example so you image size probably wont be as easy to divide by 2, but you can use math to get any image to print at Native Printer DPI.
IF you need more help, you would need more details, like what kinda image your scanning. and your Scanner/printer specs.