Air bubbles in toilet plumbing may be an indication that you need to take action immediately. Normally, air in the toilet indicates that there is some kind of blockage. Getting rid of the blockage and the air in the plumbing is a fairly simple process that you can accomplish on your own.
Fill the toilet bowl halfway. If it is completely full and ready to flood, put on some rubber gloves and use a cup to bail out half the water and anything else in the bowl into a bucket. If it is completely empty, run some water into the bucket and use the bucket to fill the toilet bowl halfway.
Apply the rim of the plunger to the draining hole in your toilet. You need to get a firm seal all the way around the hole for the plunger to do its job. Make sure it is connected all the way around.
Force the stick of the plunger quickly in and out of the rubber seal for 20 seconds. If it is sealed correctly while you plunge, the water in the pipe leading out of the hole makes a whooshing noise. If it just sounds like the water in the bowl is moving, go back to Step 2. When the water in the bowl drains, try flushing the toilet again. If it still backs up or bubbles again, go on to Step 4.
Run the guide tube of the closet auger down the drain and turn the crank to the point that it gets tight in one direction. Turn it back in the other direction until it is tight that way. Crank it back to the center and pull the guide tube out. If the water drains, try flushing again. If it bubbles or backs up again, repeat Steps 2 and 3 again. If it still fights you, move on to Step 5.
Turn the valve on the water running into the toilet to the right until it is off. Drain the toilet. If you can get it to flush, flush it. If it does not, remove the lid from the tank and siphon it or bail it into a bucket with the cup. Do the same with the bowl.
Unbolt the toilet from the floor with an adjustable wrench. Turn the toilet over and look at the plumbing to see where the blockage is clear it with the closet auger or rubber gloves. Look at the drain below it in the floor to see if it is there and clear it with the rubber gloves.
Replace the toilet with the pipes leading out, fitted over the drain in the floor. Bolt it back down with the wrench. Turn the water valve that leads into the toilet back in and flush it.