Resolution set up for print is 300 dpi (dots per inch). This allows for greater detail in the actual print out.
Resolution for screen display is 72 dpi. There is no need for screens to display your work in a higher resolution. This also work well for web, but it is generally better to design in 300 dpi then move to 72 dpi afterwards.
Colour modes should be RGB for screen and CMYK for print. RGB gives you more colours to work with, you could use this to produce your work on-screen but you will need to make sure its changed to CMYK for when you print.
Moving to CMYK can lead to color quality loss in some situations, this should be considered when designing for print.
Colours can be previewed using image mode > RGB/CMYK
Canvas size should be the preset for your artifact.
When designing for print add 3mm to EACH edge, this is due to the trim process.