Choose the dehumidifier you'd like to buy. The main differences between dehumidifiers are reservoir size and automatic features such a humidity control.
Buy the dehumidifier and set it up in the most humid area in your home. Basements are often the most humid.
Turn on the dehumidifier by following the unique accompanying instructions with your dehumidifier model.
Remove the reservoir tank when the dehumidifier fills and empty the water into a sink. Re-install the reservoir tank the same way it was removed or by following the accompanying instructions provided with the dehumidifier.