Buddhists often say that they practice Buddhism. What exactly does "practice Buddhism" mean?
First, "practice" most often refers to a specific activity like meditating or chanting that one does every day. For example, a person practicing Japanese Jodo Shu (Pure Land) Buddhism recites the Nembutsu every day. Zen and Theravada Buddhists practice bhavana (meditation) every day.
Many lay Buddhists maintain a home altar. Exactly what goes on the altar varies from sect to sect, but most include an image of the Buddha, candles, flowers, incense, and a small bowl for a water offering. Taking care of the altar is a reminder to take care of practice.
Buddhist practice also includes practicing the Buddha's teachings, in particular the Eightfold Path. The eight elements of the path are organized into three sections -- wisdom, ethical conduct and mental discipline. A meditation practice would be part of mental discipline.
Ethical conduct is very much part of daily practice. We are challenged to take care in our speech, our actions, and our daily lives to do no harm to others and to cultivate wholesomeness in ourselves. For example, if we find ourselves getting angry, we take steps to let go of our anger before we harm anyone.
We are challenged to practice mindfulness at all times. Mindfulness is nonjudgmental observation of our moment-to-moment lives. By remaining mindful we remain clear to present reality, not getting lost in a tangle of worries, daydreams and passions.
Buddhists strive to practice Buddhism at every moment. Of course, we all fall short at times. But making that effort is Buddhism. Becoming a Buddhist is not a matter of accepting a belief system or memorizing doctrines. To be a Buddhist is to practice Buddhism.