Markers are a must in your took kit. They can be super fancy or just a piece of contrasting yarn. The main point is to see it. When you have a section in your project that is different than the rest and you don't want to count out stitches every row/round, it is time to place a marker. A spot where you increase or decrease for a number of rows/rounds? Place a marker. A section of lace or cables? Place a marker. Just slide the marker or your choice onto your needle in the desired spot and carry on with your knitting. When you reach the marker on the next row/round, slip the marker from left hand needle onto the right hand needle and go on knitting as normal.