Use a third-party wishlist instead of Amazon's built-in
Why make a wishlist?
There are three reasons you might want to use a wishlist, rather than just buying things as you think of them:
To compare all the things you want, and to fit them within your budget. You probably can't afford everything you want right away, and by putting them on a wishlist and then buying the ones you can afford you can make sure (a) that you buy the ones you want the most and (b) that you remember the other ones for later, when you have a bit more spare cash.
To avoid impulse purchases. Putting things you want on a to-buy list can fulfil the shopping impulse, without actually having to buy things. You can check the list a few days later and see if it's really a good idea to buy the things that you've put on there, and avoid lots of extra tat you didn't really need showing up in your home and wasting money.
To give others ideas about what to buy for you. Since it's the giving season at the moment, people have been asking about the best way to share ideas for a secret santa or similar. If you maintain a general-purpose wishlist all the time, then you can easily share ideas.
Why don't I recommend Amazon?
Amazon has a wish list section that can help you with points 1 & 2 above. But it's a bit flawed:
You can't access it on mobile
To view other people's wishlists you need an invitation, and you cannot view anonymously.
These have been inconvenient enough that my family can't naturally use them for managing Christmas shopping, but I would guess there are also incentive problems for Amazon's wishlists. Wouldn't Amazon rather we buy buy buy instead of considering what we purchase? Wouldn't they rather keep us shopping at their storefront, instead of shopping with third parties?
What to do instead?
I recommend instead using a third-party wishlist site, which makes wishlists their primary functionality. This way they don't have incentives to keep you at their own storefront, and they do have incentives to make the wishlists easy to use and share.
While I've not explored this space in great detail, I quite like Things to Get Me, which is easy to use on the web, has a mobile app if you're into that sort of thing, and also supports funds for collecting cash for a wedding or holiday.
I'm going to be using it as a first-line for impulse purchases, which will hopefully let me get my giant book pile under control!