This is a bit tricky. It is very hard to get unless your hair is of course naturally straight. You may think about a permanent straightening product, but that may leave your hair a bit dry. If going the permanent route, a blow dry is highly recommended afterwards.
If your hair only has a slight curl or wave to it you may be able to get away with a good and thorough blow dry. Using Simply Straight™ Instant Straightening Cream will help to smooth your wave while you blow dry.
However, the best way to a pin straight look is still with the use of a flat iron. If heat damage is a concern, Marc Anthony’s Simply Straight™ Heat Protect Flat Iron Spray will help to straighten curls and waves with minimal trauma. You can blow dry or let your hair dry naturally and afterwards use the Flat Iron Spray to protect the hair before applying the flat iron tool.