A 29-year-old woman presents with a 2-day history of dysuria, urinary frequency, and suprapubic pain. She is sexually active and uses condoms inconsistently. A urine dipstick shows nitrites + and leukocytes ++. She is not pregnant and has no signs of pyelonephritis. She reports a similar episode 6 months ago. This is her second UTI in 6 months. According to NICE CKS for recurrent UTI, what advice should be given regarding prevention after this acute episode is treated?