When you think about fasting, you probably think about religion, where it is often used as a method of purification. However, too often it is construed to be a completely harsh experience wherein one simply never eats for a given period, which actually does your body harm. My fasting guidelines for dietetic purposes are much easier, not painful, and entirely healthy.
One way to fast for weight loss is to skip dinner. You don't need the energy from the meal, whereas you need breakfast and lunch for energy during the day. Space out your meals to ward off hunger as best you can: have a big breakfast early in the morning and a late lunch, and sleep early, before you get hungry. Instead of snacks, have hot tea/water to fill your stomach without adding unnecessary food. The convenience of food nowadays makes for more eating than we need. An alternative to this method is to replace all your meals with hot water/tea, or with vegetable juice.
A lot to do with hunger is in the mind, rather than the body. For example, we often get hungry at the same times every day simply because our brain comes to expect food when we usually eat. We can leverage this mental capacity for hunger to our advantage in order to lose weight, but it takes strength of mind and will. Concentrate, and visualize your stomach as small, and your meals as plenty to fill you; keep telling yourself that so your limit will eventually be diminished. Also, visualize your hot tea/water as filled with energy, bestowed by whatever higher being, to increase its effect. If you really need to, you can also visualize the air around you as swirling with energy, and gulp it down with your saliva until you feel full. Monks use this tactic to help survive during extremely lengthy periods of meditation. All of this will help you to ward off hunger.
Fasting is not for everyone, even to this lesser degree. Don't try this if you feel you'd be putting your health at risk: there are plenty of other viable suggestions in this booklet to help you lose weight.