Disclosed are embodiments of a versatile storage bag and methods of making same. The versatile storage bag may have first and second sidewalls, a double-locking closure mechanism with a first closure element extending along the first sidewall and a second closure element extending along the second sidewall, each closure element having a channel and an elongated member configured for interlocking with one another. A double-seal along three sides of the first sidewall and the second sidewall form a gusset between two seals, leaving an opening through the double-locking closure mechanism. Corner seals may be formed at the corners of the first and second sidewalls, further reinforcing the double-locking closure mechanism for an airtight and hence waterproof seal. The versatile storage bag may be made of a food-grade polyethylene vinyl acetate blend, approximately 90% or less ethylene vinyl acetate and approximately 10% or less polyethylene.