All good advice but if you're determined to go forward, there are two things to start with: one is to read through the abbreviations and learn how to do the different patterns and cables. The actual directions are minimal, just combining the cables and diamond patterns. Two is to make a gauge swatch to determine what needle size you'll need with your yarn. You may knit tighter or looser than the person testing the pattern so you may need to change needle size. Cast on about 25 or 27 sts (some odd number) and knit for 5 inches or so before measuring how many stitches you get in 4 inches. There are some good videos for getting started here
including some for gauge.