Forage a Maple Seed from trees in the Forest, Mountain, or on your farm
Plant the Maple Seed to grow a Maple Tree
Wait for the Maple Tree to mature
Craft a Tapper
Place the Tapper on the Maple Tree
Collect Maple Syrup from the Tapper after it finishes producing
Check the Secret Woods for mature Maple Trees to tap
Buy Maple Syrup from the Traveling Cart when available
Get Maple Syrup as a possible gift or reward from certain events or quests