Choose the working quantity
Gather the bags from cabinets, car boots and coat pockets. Set aside the ones that need cleaning or repair, following their care instructions. Compare what remains with the amount you carry on a normal shopping trip. Keep a little flexibility for a larger shop, but do not assume every promotional tote needs a permanent place. A manageable collection is easier to remember and bring along than a cabinet full of possibilities you never sort.
Store them by the departure route
Fold bags to roughly the same width and stand them in a shallow box or one sturdy carrier. Keep the handles accessible so you can lift the group in one movement. A basket beside your keys can work if it does not crowd the exit. If you normally shop after work, put the folded group with the things you take to work. Storage near the kitchen is less useful when you only notice it after returning empty-handed.
Include the return trip
After unpacking groceries, return the bags to the departure point rather than leaving them beside the counter. Keep any that need cleaning separate until they are ready to rejoin the set. Avoid stuffing extra bags into the middle of folded ones; that slowly creates a dense knot no one wants to open. If a container becomes hard to close, edit the collection before increasing its size. The system succeeds when taking a bag is almost automatic.