Bed bugs are notoriously difficult to get rid of, but there are several methods that can kill them instantly and permanently. Here are some of the most effective ways to kill bed bugs:

1. Bed Bug Killer Spray: Bed Bug Killer spray by EcoRaider is effective on bugs, nymphs, and eggs, and is recommended for the quickest way to kill bed bugs instantly.

2. Heat Treatment: Heat treatments can kill bed bugs in one day by a licensed pest control company. The affected room is heated to between 135°F (57.2°C) and 145°F (62.7 °C). When a bed bug (and bed bug eggs) reaches 122°F (50°C) they immediately die.

3. Rubbing Alcohol: Rubbing alcohol is a quick and easy solution for killing bed bugs. You can dilute it and place it in a spray bottle and simply spray the infested areas. The alcohol will kill bed bugs almost immediately. It also evaporates quickly, leaves no traces or bad smells.

4. Diatomaceous Earth: Diatomaceous earth is a chemical-free powder that can eliminate different types of pests, including bed bugs. It dehydrates the bed bugs, which kills them off. It may take up to a week before you see results.

5. Tea Tree Oil: Tea tree oil is an effective natural remedy to kill bed bugs instantly. You can spray the tea tree oil on furniture joints, headboards, cracks, and corners. All you need to do is to make a diluted solution by putting 20 drops of tea tree oil in a water spray bottle and shaking before using.

Its important to note that while these methods can kill bed bugs instantly, they may not be effective in eliminating the entire infestation. For major infestations, its recommended to enlist the skills of a local pest control specialist.