Start with something you're familiar with. On a warm summer day you might put ice cubes in your drink to keep it cool. Turning water into ice is a chemical process, a scientific process, that requires lowering the water's temperature enough to cause it to change phase from a liquid to a solid. Drinking a glass of cold water to keep your body hydrated and cool is a subtle but real way that science influences your body.
Use your momentum from Step 1 to ask more questions related to that particular situation. For instance, you might wonder why the body gets thirsty for cool water on a hot day. Keeping yourself hydrated is extremely important because approximately 60% of your body is made of water. Water helps your internal organs function properly, promoting favorable conditions for chemical reactions inside of your body to metabolize food, store energy and to maintain a constant core temperature. This complex chemistry inside of your body is a very important way that science allows you to live and function healthily.
Continue to ask questions about a small situation, like the ice water example in Step 1. It is easier to get a handle on ways in which science affects you if you start small. Another question you might ask on a hot summer day is, "How can the sun feel so hot if it is so far away in the sky?" The sun is a powerful source of radiant energy which it is capable of transmitting through empty space to the Earth. Radiation is just one way that heat is transferred from one object to another. You'll notice that a radiating heater in your home manages to heat entire rooms. The sun is like a much bigger version of that heater; in fact, it's so powerful that it is capable of heating the entire Earth. Heat transfer is an important part of science that affects what clothes we wear and even how we feel on a given day.
Use new discoveries to ask other questions about how science affects you. You might wonder how the sun affects trees, or how trees affect humans. Investigating these ideas further will show you more about how science affects life in millions of ways.