There are so many variations on the incubator theme than it is hard to say what is "best".
I tried the aquarium and heater method once, but it was in a cool part of the house, and there was severe temperature stratification between the bottom and top of the tank. Insulation might have solved that problem, but I didn't try it.
For many years, my "best" method was to put the eggs up in my house's second floor, which was quite warm.
A heat pad in a styrofoam fish shipping box from a pet store or a cooler from the local discount department store might work for you.
Remember, all the incubator box must do is hold the heat in. I put a closed plastic storage box in my incubator to hold the humidity, and a plastic shoe box inside the sweater box holds the Vermiculite and eggs.
Some people like a Hovabator, but it is too small to hold my storage box.
Hope this helps.
Paul Hollander