Create your own problem: n nodes, m edges. Color each node red or blue such that each edge has at least one red endpoint. Model: x_i is true if node is red. For edge (u, ), add clause x_u OR x_v. Implement the full -SAT algorithm and test on small graphs with different structures.
This builds intuition for how -SAT expresses constraints. Try different graph structures like trees, cycles, and complete graphs to see when solutions exist.