What you need to do is get a grip on the little guys before they arrive. The first step in any good skin care routine is cleaning. Cleaning your face at least three times a day, especially when you travel a lot, is a good habit. Because pollution adds to the grime and dirt that encourage acne. Try and use a cleaning agent other than soap, like a mild face wash, soap-free or herbal products.
Pimples begin when oil and dead skin cells get trapped in pores.
So you've got to use products that work inside the pores to help keep them clear. Using a scrub once in three days would be a good idea. Being regular in your cleaning habits, even when your skin looks great, will help prevent pimples. Try using a cream or mosituriser that absorbs excess oil, and is not oily itself. Once the zits pop up, use of an anti-pimple cream or lotion is not a bad idea, but do so only after having read the instructions carefully.