Splash Woman and Concrete Man
Starting off with Splash Woman, you need to begin shooting her immediately and keep below her vision level. The fish at the bottom need to be shot, especially when they fly across the screen as Splash Woman sings and shoots laser tridents. She charges at you and you will need to keep your distance while shooting.
Next comes Concrete Man. The trick here is to use the laser trident to defeat him. You need to jump over him as he charges at you and shoot back in the direction he is running, which will be behind you now along with jumping whenever he is looking to cause an earthquake.
Galaxy Man and Jewel Man
These two bosses are the next up in line. The Concrete Shot will help you in defeating Galaxy Man as you will need to fire at him while he charges at you. Be sure to keep away from the back hole he fires and fire at him again when he is down and out.
Using the black hole bomb is a sure way to defeat Jewel Man, but stay away from him as far as possible and fire again when the bomb is nearly approaching him to make an explosion that makes a needful impact.
Plug Man, Tornado Man, Magma Man and Hornet Man
These four bosses are the last in line and in ascending order. Gaining the Jewel Satellite will allow you to beat Plug Man, followed by using the Plug Ball to defeat Tornado Man. The Tornado Blow will beat Magma Man and the Magma Bazooka will defeat Hornet Man.