Hundred ways to do it, they all have their pros and cons.

Breaking up by brand then sorting alphabetically is probably the best way for mixing known recipes.

I prefer to sort by the individual dominant flavor or profile but that's a call I made out of a sense of creativity, figuring it would be easier to find something that fit an idea if I went to the bin full of strawberries when I want to make a new strawberry recipe, etc.

So my flavors are sorted into trays based on the profile. So I have a seperate bin for citrus, strawberry, blueberry, melons, breads, cereals, chocolates, coffees, booze, caramels, etc.

I sort mine by throwing them all into one huge draw and when I need to mix up I spend 10 minutes rifling through them till I find the one I need and repeat till all flavours are found. It's not perfect and it's not efficient but neither am I.

I started out using the shoebox method very similar to u/saspi25, but as I got more and more flavors it became increasingly harder to keep them organized in a fashion that I could locate individual flavors. It got to the point where it would take me 10 minutes just to locate favors for a mix.

I recently picked up some hanging jewelry organizers off Amazon and have them hanging in the closet in my office now. It's worked extremely well so far.

https://imgur.com/a/8yJeiMe

your friend

I just spent the last few weeks doing exactly this... These are definitely the best Containers I could find online for storing my flavor bottles. They are a good height, pretty cheap, and a decent size for storing your flavor gear in a limited space:

https://www.amazon.com/gp/product/B083JXHCR3/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

I cut a cardboard box into dividers to organize them further...

What size bottles?

I have small shelves that hold my 200 flavors. They are organized by brand and in alphabetical order. Makes it really easy to find my flavors when I'm mixing recipes.

I have about 100 in a box. As a huge LEGO fan, part of the fun is hunting for flavors and being able to recognize flavors/brands while digging through the box. I would definitely suggest either sorting by flavor profile, use (sweetener, primary flavors, secondary/additive flavors, etc), or by recipes if you aren’t like me though.

I started out sorting them by brand but I switched over to sorting them by flavour. It took me all weekend to re-organise them, but it was worth it. I've found it so, so much easier and quicker that way. When I had them sorted by brand if I wanted to make a custard for example I would spend ages going through boxes trying to find all the custard flavours I had. I'd end up forgetting I had some stuff and wouldn't use it.

Now if I want to make something they're all there and I can quickly and easily see the options I have for a recipe. It also helps when I'm mixing something and I'm not sure what it needs. I can look at all the labels on the boxes and it usually gives me some sort of inspiration. There's a couple of annoying flavours that don't fit into any category, but not many at all. Cos I'm cheap and they fit perfectly on my shelves I just used the cardboard boxes Chefs have sent flavours I've ordered in.

I used to put them into tiny plastic bags, with all required ingredients for a given recipe. That meant that I had to have a lot of flavors multiple times.
Now that I started doing premixes, I simply toss them all into a huge zipper bag, one for each brand.

I have two of those dinky little drawer/tray things, like a student might keep their papers in for Chem, Bio, Science, English, etc. In the drawers I lay them flat (lids on tight), separate rows with little cardboard dividers made from cereal boxes or whatever. I go alphabetically first. Capella Vanilla Bean Ice Cream comes before TFA Vanilla Bean Ice Cream, and then there's Vanilla Cupcake and Vanilla Custard. I don't separate out all the Capellas etc and keep them together, though that makes sense too. I have about 200 and this works so far. I keep back ups in the last drawer so I don't accidentally open the new one before the old one is used up.

I Keep them in shoeboxes, sorted by flavorhouse. On top of each flavor I put a small sticker with a number. Keep a list with number/flavor on a word file. So let's say I'm looking for flv cured. Search for cured on the word file, see the associated number and just pick the flavor from the flavorah box. Easy peasy

Aside from sorting, one thing that will likely be useful is keeping track of how much of each flavor you have left.

I was like you, I started just buying a whack-load of 10mL bottles with the thinking of "if I end up liking it, then I'll buy a bigger bottle", but over time I forgot which ones I used a lot until going to actually use them and finding I didn't have enough to mix with.

SO, keep a spreadsheet of which flavors you bought, when you bought them, the bottle size, the weight they were when full (that way you can subtract the empty bottle weight and know how much actual liquid you have left), and try to always remember to tick off how much you use when you use them (you might forget every once in a while).

That way, when you're going to pick up new flavors, you can sort your spreadsheet and easily find the flavors you use a lot and are low on to restock.

It might not seem too important yet, but as you start collecting more and more flavors in more and more bottle sizes, you might find you have duplicate bottles of some flavors, and some flavors that you just know you had but can't find anywhere.