Drink plenty of water. Avoid drinking coffee, tea, alcohol, and cold beverages. If possible avoid sexual intercourse during an infection. It is best to avoid eating raw or uncooked foods like salads and sushi; greasy foods like cheese and chips; and pungent or heavily seasoned foods like curry and barbeque. No chocolate. No smoking. Exercise daily to keep your body and immune system strong.
For prevention, empty your bladder as soon as possible after sexual intercourse.