Reduction linocuts are printed from one piece of lino, cutting it again for each new color in your design. All the prints for an edition have to be printed before you move on to the next color, because once the lino is recut you can't make any more. Depending on how many colors you use, at the end there may be very little of your lino block left uncut.
The first cut is for any areas in the design to be left white (or the color of the paper), and you print it with color #1. The second cut takes away those areas in the design you want to be colour #1 in the final print. You then print color #2 on top of color #1. (Ensure the ink is dry before printing the next color.) The result is a print with white and two colors.
You can keep going for however many colors you wish, but the more you use, the more carefully you need to plan. One wrong cut, or one forgotten cut, could ruin the design. Add to this the challenges of ensuring each color is correctly registered (aligned) when you print it and I'm sure you'll begin to see why reduction linocut is also know as suicide printing. However, when things do all work out, the results are tremendously satisfying!
As with anything new, start with a simple design and get a feel for the technique first. Plan your design using layers of tracing paper, one for each color, before you start cutting. (Remember the paper color too.) When you've recut the lino, do a test print on a separate sheet of paper to ensure the cut is how you want it, before printing onto your actual prints.
Ensuring that the colors are aligned properly takes a little practise, so always print some extra prints to allow for misprints. You can do it by eye, carefully putting the paper down onto the block. More reliable is to make a registration sheet with outlines of where to place the linoblock and where to place the paper. You put the inked lino in place, then carefully align one corner of the paper with your marks and gradually drop it down.
: See also: Step-by-step examples of intricate reduction linocuts from printmaker Michael Gage