By Ariane Sohrabi-Shiraz Walking is an often overlooked form of exercise, but with the right technique you can increase the amount of calories you burn, which aids weight loss. You should aim for 150 minutes of weekly exercise, according to the NHS, but it can be hard to fit in gym sessions between getting the kids ready for school, going to work, picking them up, making dinner, putting them to bed – and then doing it all over again. Gym memberships can also be expensive, and not everyone feels comfortable going. But it doesn’t have to be hard to build stamina, burn excess calories and make yo…