
Sure, you can tweak your photos after the fact to make them as colorful and as bold as you remember them. But that adds a step to your post-production as you tweak it get exactly what you want. If you get to know your DSLR's settings, the photos you get coming out will already have that vibrancy.
Your mileage may vary, but virtually every DSLR I've used has custom settings that allow you to adjust Contrast, Sharpness, Color Tone and Saturation. Saturation's the important one here. Bump it up a few steps and you'll have bold, powerful colors in every shot you take.
One caveat, don't use this setting for taking portraits or shots of people where their skin is a big part if the photo. They'll look orange.