Our web diva's mom is great when it comes to shopping.
She has used this secret for years to help her score some great deals when it comes to gifts for friends, realtives and especially herself.

Google Calendar, Smart Devices or if you don't have access to those, a handy purse sized notebook that you can get from the Dollar Store, Dollar Tree, Walmart works good too:

Create a note that has all of your families, friends clothing and shoe sizes in it.
She also recommends putting in color and style preferences if available. 
Some will wear hats, some will never wear orange, you know the drill.

That way, during the year, as you see sales, you can snatch up anniversary presents, birthday gifts, thinking of you gifts, V-Day gifts, office holiday exchange items, stocking stuffers, etc. without stressing out about it.

As you pick up items, you can place reminders on the calendar a few days before the event saying that you have it taken care of. 

If someone is losing weight and the outfit won't work, most stores have a no hassle return policy as long as you keep the reciept or have a gift reciept attached with it.
If the store won't take it back, our web diva's mom recommends, keeping it for herself or if not her thing, sees if she can consign it and get either cash back or credit at the store.

Sometimes she actually has made money this way!

She does the same thing with holiday cards, birthday cards, etc.
Buy them in bulk when they go on sale (after the holiday is over), organize them in a standard filing box by month and or holiday and you are good to go.