The Node Mazes use winding pathways to go from one large node (indicated by a circle) to the next. They sort of look like computer circuitry. To make the pathways more clearly defined, when one path dips below another, two small circles are used to represent the dip. Just jump from one small circle to the next and keep going. The only times when you (may) have to choose from a few different paths is at a node.
Notice that at the start, you have two choices, one going to the left and the other to the right. Below the start node is an incoming path. There are a total of five nodes here, including the start and finish nodes. The solution path below is marked in a different color, and passes through all but one of the nodes.
Because all of the nodes are connected, try and find the path from "s" to "f" that goes through the fewest number of nodes. A good way to accomplish this is to try to avoid revisiting nodes.