Eliminate alcohol consumption. Most alcoholic drinks are high in calories, dehydrate your body, slow your body's ability to metabolize carbohydrates, and make you hungrier. All of those attributes will work against your fitness goals instead of enhancing them. The body also treats alcohol like sugar and spikes the hormone insulin which contributes to gaining fat. Consuming alcohol + sugar = insulin spike which = weight gain
Cut the soda and diet soda drinks. Drinking soda and other sugary drinks is a quick way for those empty calories to sneak in and add up. They also contain a lot of sugars and/or artificial sweeteners that your body does not need.
Keep cold water ready to go in the refrigerator at all times. Water seems more appealing and refreshing when it is cold. Invest in a reusable water bottle and keep it filled and chilled so it is readily available when you need it. If you need some kind of flavor or carbonation try buying seltzer, adding lemon or other fruit to your water, or invest in a Sodastream machine which will give you on-demand carbonated water whenever you want it.