How to Increase BMR

Walk for 2-5 minutes after getting up in the morning. Walk at easy pace. Walk within your house.
At the end of walking you should be full of energy. So depending upon your age and health, you may walk only for 2 minutes. This is called surplus energy mode.
After walking get in the bed again for 10 to 15 minutes. Close your eyes and be in complete rest position. The excess energy produced by walking will be used by your vital organs. The excess energy available in the body due to walking must get used by vital organs. So complete rest is necessary after walking.
Repeat walking and rest 4 times in the morning and 4 times at night before sleeping.
Walking during work hours will not count.
Walking more than 5 minutes is bad for health. Walking for longer duration will leave your body in energy deficit mode leaving much less energy for vital organs. That will further slow down the metabolic rate.
The above will increase your Resting Metabolic Rate also known as Basal Metabolic Rate (BMR).
Diabetes, BP, Heart Diseases, stroke, kidney failure, migraine, PCOS etc (And this is a really long list) are all metabolic syndrome diseases. Metabolic syndrome means your vital organs are not getting enough energy for your vital organs.
So drive more energy to your vital organs every day.

I personally recommend eating 1/2 small spoon of sugar 10 times a day.