These can be found at most convenience stores or on eBay. Decide yourself if you want multiple or one large one. Do you want it camouflaged or it to be a bright color? It's all up to you.;
, Most modern canteens have a lid that you twist left to open, but a few go for that rustic look by using a cork. Keep your lid/cork intact though, don't accidentally through it away!

, Tilt it at a 90 degree angle so that you can get the most water in. In place where water is scarce, consider putting another container under it to prevent water wastage.
 With lids, twist it right until you can't twist it any more. For a cork, pop it in as far as possible while able to get it back out again.
Acquire a canteen.
Unscrew the lid or pop out the cork.
Pour water in it.
Securely put the lid/cork back on.
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