OK, so please, please, please, poke nothing into your ears. If you must try then use your elbow. Hot bath or shower will get rid of most excess wax in outer part of ears.
The popping and temporary deafness is caused by inequality in air pressure on either side of the eardrum, and this is normally regulated by a link from the inner ear to the back of the nasal catacombs called the Eustachian tube. When this is restricted the pressure can't equalise. The water gulping trick is good for relief, but a longer term remedy is to reduce your intake of milk (I jest not!) and dairy products. The sinus congestion will decrease after a week or so.
This trick is well known to professional singers, whose clarity of voice is adversely affected by dairy produce. (Please, no quips about cows and fat ladies at last singing!)