Touring Costa Rica in one day is as good as just going through all the possible destinations to visit via a high-speed sports car. It's just impossible to make a sensible tour in 24 hours and claim to have enjoyed it. There are just so many things to discover and appreciate about this place that all those wonders cannot be just compressed into a single day.
But if you really do not have that much time, and you only really have a single day to spare, what shall you do? Since you really cannot do everything that is possible, which department can you concentrate on? I noticed that there are a lot of Costa Rican one-day tours that can be seen in the Internet. Whether you want to have a canopy tour of the Costa Rican forests, or you want to make that tour scuba diving and seeing the wonders under the sea, there surely is a day tour package especially fit for you.
One set of Costa Rican day tours can be found here at CentralAmerica.com. The tours here start from as little as $37.00. There's a complete San Jose shopping tour, a tour of Irazu Volcano, a scuba diving day tour, a visit to Poas Mountain, the oxcart factories, and similar items. You can check out the full ticket in their website.
Meanwhile, the day tours in CostaRica.org are more centered around different activities, as opposed to the previous one's concentration on the location. In the latter, there are also tours for scuabe diving, canopy viewing, surfing tours, canyoning tours, etc. Choose your tour based on your interests and where you think you are good at.
We are not given much time on Earth. Let us make the most out of it. If it's only 24 hours we have in Costa Rica, then make sure that this 24 hours are worth remembering over your lifetime. An organized tour should be in order.