Tripod is a must, also you have to have a camera (or app) that will give you long exposure times.

For instance, this here is a ten second shot. Four seconds is about the minimum if you want the full hit.

(Edit) Littletranspunk has an excellent comment here with advice as well, thanks for that!

This was a Lumix S5, vintage Vivitar MC 70-210mm. Manual focus and locked at f/12

Depending on how much of the explosion(s) you want recorded, make your exposure time longer and adjust aperture depending on how much light you want in each shot (smaller for longer exposures)

When I did photography, I used 1-5 second exposures and adjusted aperture if it was too bright or dark (don’t remember the aperture settings)

A tripod or some method to keep the camera still is a given for longer exposures.

It can be done with SLRs, DSLRs, and advanced camera apps, but the quality of the device and internal camera hardware with phones vary so, professionally I’d recommend an SLR or DSLR camera, unless you have a phone that’s great for those kind of photos

Edit add: ISO setting should almost always be low (250 or less is best) to prevent noise

Lock focus because auto focus for this kind of thing will almost always result in blurry photos