Fair Isle charts are read right to left on the right side, and left to right on the wrong side. If you're knitting in the round, though, then every row is read from right to left since you're always knitting on the right side.
Each block represents one stitch. A chart will either be in color or will have symbols to represent the colors--with a key. Sometimes it helps to color the chart or the key to make it easier to follow--at least until the pattern establishes itself.
Keep your stitches stretched out on the right needle to prevent puckering, and be consistent with your colors--keep the background color as your top yarn and the contrasting color as your bottom yarn. What that means is that when you have two colors traveling across the back, one will be over the other--horizontally. Just try to keep them that way so you don't end up untwisting yarn later on.
"Trust the pattern!"
Time flies like an arrow, but fruit flies like a banana.
Hop aboard while we follow the cloud-covered van of knitting harmony, man!! Woooo!! --Hedgehog
IngridKH on Ravelry