You don't open the valve and then pump the brakes. That makes air suck into the system. That's probably why you have to buy that tool, cause you don't know how to do it right. Anybody can gravity bleed or pressure bleed a four wheeler by themselves. It doesn't take an act of god, or getting the wifey to help you. Here's a step by step instructional for both.
Pressure Bleeding:
1. Fill the resevior, and tighten cap. (Cap must be on to properly pressure bleed)
2. Pump the pedal/handle until you feel some pressure build up. (Should be at least 15-20 times for first bleed)
3. Hold the pedal/handle all the way down. (During the next step, the pedal/handle will lose all pressure. Keep holding it down)
4. Crack the bleeder valve slightly, where fluid can ooze out. (Do not open it so that fluid shoots across the room)
5. Slowly release the pedal/handle. (Doing it fast will cause air to backfeed, or enter through the resevior)
6. Check fluid. Refill and tighten cap.
7. Repeat steps 2-6, checking for bubbles in the fluid coming out of the bleeder valve, each time that you repeat the process.
Gravity Bleeding:
1. Fill the resevior, and leave cap off. (Leaving cap on is like filling a bottle with water and flipping it over. It makes bubbles. Make a vent, and it flows)
2. Take the bleeder valve completely out of the caliper. (Allows for air to escape more easily)
3. Let the system bleed on it's own for approximately 30 minutes, refilling the resevior as needed.
4. Replace and tighten the bleeder valve.
5. To get maximum pedal/handle pressure, pressure bleed at least one time.
**During both processes, you can take a wrench and tap on the caliper, master cylinder, and hoses, to help push air bubbles to the bleeder. Both processes are a good way to bleed a brake system. If you follow the steps exactly for either one, and still can't get pressure, then do the other.**