CRISP — the five-cell path
Trace CRISP through 1 at row 5, column 1; 2 at row 6, column 1; 3 at row 6, column 2; 4 at row 5, column 2; 5 at row 5, column 3. Reading those cells in order gives C → R → I → S → P, so both the spelling and the five-cell length match.
Move down, right, up, and right. The route changes direction at every step, producing three turns and four straight segments across a two-row, three-column span. It visits three edge cells and one corner cell. Once these five positions are assigned, 23 of the board’s 28 open cells remain for the other paths.
Check this trace by watching its alternating movement rather than relying only on the letters. After stepping down from row 5, column 1, the route turns at each new cell until it finishes at row 5, column 3. A second step in the same direction would no longer match the recorded shape.