Upgrading from Perch 2.4.9 to 2.6?

I'm getting ready to attempt an upgrade from Perch 2.4.9 to 2.6. Upon review of my installed apps, here's what I'm currently using:

Perch Forms 1.7 Perch Gallery 2.8.2 Perch Blog 3.8.2

I want to make sure I don't screw this up. How should I proceed? What upgrades do I need to make and in what order. Are there any template changes I need to be aware of to avoid disaster?