Replacing wiper blades is one of the easiest DIY jobs on any car, and doing it yourself takes a few minutes and no special tools.
First, lift the wiper arm away from the windscreen until it locks in the raised service position — most cars do this automatically or with a small button near the pivot. Look for the small tab or clip where the blade attaches to the arm's hook; pressing it releases the old blade, which then slides off the end of the arm.
Slide the new blade on until it clicks into place, making sure the connector fully seats — a loose blade will rattle or detach at speed. Gently lower the arm back down onto the windscreen (never let it snap back on its own, which can crack the glass).
Repeat for the second blade, then test both with the washer fluid running before you actually need them in traffic. Most cars need this done every 6–12 months, sooner if you notice streaking, skipping, or a squeaking noise during use.