From Longman Dictionary of Contemporary Englishsmarten something ↔ up phrasal verb especially British English1 SMART/WELL-DRESSED smarten yourself up to make yourself look neat and tidy You’d better smarten yourself up.2 TIDYto make something look neater We need to smarten the place up a bit.3 smarten up your act/ideas to improve the way you behave or do something The company needs to smarten up their act if they are to keep customers. → smarten→ See Verb table
Examples from the Corpus
smarten up• Andrew Lloyd-Webber's new wife, horsewoman Madeline Gurdon, has tried to smarten him up.• It's been compared with New York's notorious Bronx, but now the council plans to smarten it up.smarten yourself up• Jeremy, go smarten yourself up before dinner.• She's smartening herself up in the ladies' room.• Smarten up! It's time for inspection.smarten up your act/ideas• Despite the encouraging figures, the Chunnel has prompted ferry companies to smarten up their act, and offer better deals. 