If you don't have one, get one of those 'bottle-blasters' or whatever they call it. I'd link to on on amazon, but their links are often redirected if read in another country so here's a duck-search page full of them:
https://duckduckgo.com/?q=blast+bottle+washer&t=ffab&iar=images&iax=images&ia=images
If PBW isn't available to you, I'm surprised no one has mentioned this thread yet;
https://www.homebrewtalk.com/threads/homemade-pbw-recipe.467655/
I keep a simple bottle washer hanging on the side of my laundry tub;
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I always hated the idea of throwing out a batch of PBW after cleaning my equipment...having removed all visible solids and rinsed everything before the PBW cycle it just looked 'too clean' to throw away after one use, so always keep a few gallons or so in a large picnic-cooler under the laundry-room table. My bottles, after use, get blasted out with hot water and then I simply drop them into the PBW in the cooler for a day or so...when I have a few in there, I just take them out and thoroughly blast with hot water, inspect, and then put them on dishwasher rack to dry...when dry, I tear a piece of cheap basket-type coffee filter to put over the top, held on with a tin-tie to allow breathing and prevent dust and such and put them in their box. When I need them again, They're already set to be dropped in a bucket of Star San and then refilled.
The cooler full of PBW also gets some of my SS and glass cookware when I have burnt on crud..a day or 2 of that and they come clean as new. ..of course I do not mix cookware with bottles for contamination risk..but it's a convenience to have around.