Taste a few grapes that look ripe to verify they have reached the sweetness and maturity you prefer. For best results, sample some grapes from each of the clusters you want to harvest as tasting is the best way to judge ripeness.
Remove any netting or protective bags you've used to shield your grapes from birds and other wildlife. Set these aside to use next grape season.
Pull the grape cluster toward you gently without disrupting the vine growth or uprooting the plant.
Position your small curved grape knife with the inside curve of the blade facing the stem. Use small pinking shears if you prefer.
Cut downward to remove the cluster away from the branch, leaving a 3- to 4-inch stem on the cluster.
Place the grapes into the box and continue to harvest your grape clusters. Do not stack the grapes, as this can crush them; simply place one layer in a box, then get a second box if needed.