1. Prioritise
Avoid putting the important stuffs off until later. List them down and get them done first whilst you are at your most alert. Doing the crucial work first might just give you the adrenaline rush to kick off that possibly latent working spirit.2. Snack Right
Avoid a full stomach at all costs; being full will make you more sleepy than you already are. Instead, munch on small snacks throughout the day. Snacks like sunflower seeds, biscuits, raisins and nuts will require you to perform some simple movement that prevents you from dozing off. Be careful not to disturb your colleagues while chewing though.3. Drink Up
Not coffee though. Drinking a glass of ice-cold water refreshes you instantly and makes sure you get up for the washroom every now and then. In the washroom, you can also splash some cold water on your face or even brush your teeth to feel even fresher.4. Look on the bright side
Adjust your seating to as much sunlight as possible. We all have an internal clock that is somehow regulated by our environment. If it is not possible to get more sunlight in, you should get a desk light such as a lamp or even some plants to brighten up your work desk.