Where are you located? Air pressure is more of a consideration for those Northwest US area inflatables for 2 reasons- sun's heat (vs. cold ice melt water) and driving to high altitude waters can increase pressure to point of bursting. So the pressure may have to be adjusted frequently depending on being in the water or not. Texas is mostly flat by comparison and water is not as cold in Summer, so only extreme heat can be much of a factor, unless the craft is used in Winter.
The maximum inflation pressure must be known for inflatable craft. It is usually around 2 psi for fabric and around 3 psi for PVC reinforced shells (much higher 6+psi? for drop stitch SUPs). Reduce the MAXIMUM pressure by about 1/3 if your pontoon will be exposed to the sun especially out of water (ie. 1.3 ! and 2.0 psi). A volleyball pressure gauge can be adapted, but special low psi gauges from marine stores are better. Pressing in hard with your thumb in the TIGHTEST area of the pontoon also works with some practice- maybe goes in about 1/4" at maximum pressure for my tube. A normal person can produce about 2 psi breath inflation with maximum effort, for reference.
If the water is Winter cold where I launch, I will go to slightly over maximum pressure because of the shrinkage that occurs with cold water. It is not a good idea to have creases in either toon because that can affect the weight capacity, balance, control and might be dangerous if one toon starts to fold over. On my 2 PSI ODC tubes all my valves except the seat back are within reach, so I have rigged a mouth tube so that they can be adjusted while on the water.
Hope this helps.
More critical than watching the air pressure while on the water is keeping it low enough while traveling in a hot vehicle...or storing it in a hot garage. Always a good idea to travel with lower pressure...and to store partially deflated. Much easier to top off the pressure when ready to go fishing than to discover a split out air chamber when you get there.
Also if a boat feels tight in the heat, put it in the water while you get your gear together then check it again.
I have seen a lot of boats under inflated.
Like TD said, no wrinkles. Use to say, bounce a quarter off them.
There is an air gauge for pontoons. It is great for getting exact air in both pontoons (like car tires).
Those are vinyl bladders which are a little more susceptible to altitude and temp. change.
The K-pump is all hand operated which means you can use it out on the water. They are pretty nice.
I pack one with me always.