The first way equalization of the middle ear

Pinch the nostrils with your mouth closed. Then shortly blow out through your nose with nose and mouth closed. Air cannot get through a closed nose and mouth, so you'll hear a distinctive hissing sound of air passing into both middle ears. The sense of relief in the eardrum or sinus is a sign that you have performed the maneuver correctly.

Other methods of equalization of pressure in the middle ear

Other methods of equalization of pressure are efficient in some people, but not in all. You can try to chew, yawn, swallow or drink small sips of water. The sense of relief in the eardrum would be a sign that you have performed the maneuver correctly.

Tubes for equalizing pressure in the middle ear cavity

If you can in no way equalize pressure in the middle ear cavity, the physician will install a tube in the eardrum, which will allow pressure equalization without your active participation. (The process of installation is painless and very simple, and extremely rarely results in complication.) Tubes will be removed after treatment cycle, and the mini holes in your eardrums will heal spontaneously. If you have tubes for pressure equalization installed in the middle ear cavity, you need to strictly adhere to all advices given to you by your doctors and prevent the penetration of water and dirt into the middle ear. If any problem with embedded  tubes will show up at any time, you are obliged to inform your physician and/or inside tender immediately.

Equalizing pressure in sinuses

Sinuses are spaces in facial bones filled with air. Air pressure inside them must be the same as the ambient pressure inside the chamber, so the same need for pressure equalization applies here, too. Otherwise, severe pain might occur. Under normal circumstances, the equalization occurs spontaneously and without any difficulties. If there is even the slightest problem or pain when the pressure inside hyperbaric chamber is altered, please inform the inside tender immediately.

Links:
equalization of pressure middle ear