How do I use multiple slide masters in a presentation?

[Geedavey]

Powerpoint 2002: I want slides 1 and 3 to use master slide pair "a" and slide
2 and 4 to use master slide pair "b".

 

[PPTMagician]

Hi,

Click on Format, Slide Design
The Slide Design choices should be on the right, click on the drop down
arrow with the design you want and choose apply to selected slide. If you
want to change the slide to a title slide, click on Format, Slide Layout and
choose the first one.

So, if I'm interpretting your question correctly:

From Slide one, click on Format, Slide Design, choose the drop down arrow
next to the Master Slide Design "a" and choose apply to selected slide.
Click on Format, Slide Layout, choose the drop down on the Title Layout and
click on apply to selected slide. Repeat for Slide three except choosing
Master Slide Design "b". Repeat for slides 2 & 4 except choosing the Title &
Text layout.

Hope this helps,
Glenna