There are many simple relaxation exercises that can be learned easily and are very effective. If it is convenient and safe to do it, and you have a few spare moments, you can get started now.
Close your eyes and take a couple of deep breaths. Take yourself to a relaxing place in your mind and spend a minute or two there. It can be anywhere you like, but somewhere you feel comfortable, peaceful and relaxed. It might be somewhere you have actually been, or an imaginary place, such as a mountainside, field or beach. If you feel resistance or interference from outside distractions or thoughts then take yourself further into that place.
Only do this exercise if it feels nice and comfortable - you certainly shouldn't be doing it if you are driving or if your full attention is needed on something else. But a minute or two doing this everyday is all it takes.
Stress is a medical condition and it can have a serious effect on your health. If you think you are suffering from stress it is crucial that you consult a medical professional.