For those with bags without compression straps, a simple hack to compress your bag, just use a belt with buckle. This is decathlon NH500 escape 32L, great bag but no compression straps.

Hiking backpack 32L - NH Escape 500 - Decathlon

Quechua NH Escape 500 Review

Ayaport Utility Straps with Buckle 48 Quick-Release

Hiking backpack 32L - NH Escape 500 - Decathlon

Hiking Backpack 32 L - NH Escape 500 Black - black, Hazelnut

Quechua NH Escape 500 32 L Hiking Backpack

New Quechua NH ESCAPE 500 lightweight hiking backpack

Carrying Strap with Handle, 2 Pack Adjustable Nylon Belt for

Hiking backpack 32L - NH Escape 500 - Decathlon

Quechua NH Escape 500 32 L Hiking Backpack