Spot the site in your house which is infested with termites or where you suspect the termites may be traversing.
You can also make your own borate solution by mixing 1 part of boric powder and 4 parts of water. Spray it over the nest for a few days to wipe out the termite infestation.
Apply some boric powder (easily available in any departmental store) to that spot. Use the powder duster to apply the boric acid powder on the marked sites.
If you manage to locate the termite colony, you can apply the boric acid powder directly on it. It will take nearly 3 to 7 days to terminate the entire infestation. Make sure you powder the nest daily.