Labyrinth fishes that build a bubblenest are found in calm water with no or very minimal surface turbulence (think a puddle). The water is usually shallow and warm and might have some floating plants. In an aquarium, you need lots of floating plants, minimal water movement, virtually no surface turbulence, and water that is around 12-18 inches deep, depending on species. Smaller species like Betta splendens prefer shallow water 6-10 inches deep (high). Pearl gouramis will breed in water that is 10-18 inches deep (high).
Feed the fish well for several weeks and have the water warm (28C). The male will set up a territory and build a bubblenest among some floating plants. He will guard the nest and area around it, and drive other males away. If he sees a nice female, he will display to her and try to entice her over to his nest. If she is ready to breed (is full of eggs) and likes him, they will breed. The eggs get laid in the water column, collected up by the one or both parents (usually the male) and put in the nest. When they have finished breeding, the female leaves the area and the male looks after the eggs and developing babies. He also looks after the fry for a couple fo weeks after they hatch.
The baby fish are very small and need green water and infusoria for the first few weeks of life. Then they can be offered newly hatched brineshrimp and microworms. But keep them on the green water until they are all eating the brineshrimp.
Info about culturing food for baby fish is at following link.
STARTING OUT Make sure you have a pair, (1 male + 1 female). There is nothing worse than spending your hard-earned dollars buying a couple of fish to try and breed and ending up with a pair of fish of the same sex. Let's face it, to reproduce fish you need a male and a female. Two males won't do...