If you think you might want to keep the design you've created for your presentation and use it again, it's worth turning that slide format into a set of master slides that you can use again and again. In other words, you want to create a Theme. Under View, select Show Master Slides so you can see the current batch of master slides. In turn, select and then edit each master slide so that it has the appropriate colors, fonts, and miscellaneous images, such as logos. You can also delete any master slides you're not going to use.
One simple, but effective, trick is to place the company logo at the same place on each slide. To ensure that only the title slide has the logo at 100% opacity, reduce the logo's opacity to 50% or less on all other slides. This keeps the slides coherent with one another, but prevents the logo from clashing with the other, more important, bits of information on these slides.
Once you're done, choose Save Theme from the File menu. Now, every time you open the Themes window in Keynote, you can select your new theme immediately and have a pre-formatted set of slides matching your own particular needs.
Figure 2: Edit the master slides to create a template that includes your preferred set of colors, fonts, and visual ornaments such as logos.