Change colours, fonts and line work on a PPT set of slides

I have a deck of 49 animated slides that show graphs building. I wish to change the colours, font sizes and line-work to match the design shown in the first slide. It is critical that the way the slides are animated and the order of the animation remains the same. It is also critical that when the same concepts appear (such as 'clean water' and others on slide 7) that the colours match. It is also important that the numbers and text shown are as close to the line they relate to and are as legible as possible. The PRAXIS brand stays as it is. Needs to be completed by COB Friday 10th, Sydney time.