A 6×6 grid is small enough to scan quickly but large enough for deductions to interact across the board. The best approach is systematic: establish the fixed values, identify restricted cages and repeatedly cross-check rows and columns.
Build a map of missing digits
For each row and column, mentally track which of 1–6 are still missing. A cell is never considered in isolation; its legal digits come from the intersection of its row, column and cage.
Prioritize information, not location
Do not solve top-to-bottom. Move to whichever cage or line currently has the fewest possibilities. A nearly complete column on the opposite side of the grid may unlock the cage you were stuck on.
Use cages as combination filters
List only combinations that can reach the target, then reject any that repeat digits already used in the relevant rows or columns.
Recognize the endgame
Once several rows have four or five fixed digits, completion accelerates. At that point, row and column missing-value logic often becomes stronger than the cage arithmetic itself.
Put the idea into practice
The fastest way to understand the interaction between row, column and cage constraints is to solve a board. Start with the free practice puzzle, then enter the live world when you are ready to race for Discoverer.