1 Use unchlorinated water
2. Place weeds or grass in it, letting it sit for a week. That gave micoorganisms a chance to grow and the water got sort of cloudy.
MAKE SURE THERE IS A LID ON IT SO LARVAE DO NOT GROW
3. Pour polluted water into small bowls.
4. Place around yard so mosquitoe come an lay their larvae / eggs.
5. Dump the water weekly onto dry surface, to kills them, and refill.
The shortest time in great conditions mosquitos can go from egg to adult is ten days, so dumping traps once a week works great.
DO NOT GO FOR OVER A WEEK OR YOU ARE GROWING MOSQUITOES