[@Crimmy]: They're typically "lots of light, girl floats around, her clothing somehow goes away and gets replaced with her magical girl outfit" but they vary a lot within those bounds. Like what causes the clothing to go away(fire is an example of something that Akane's probably going to have) and that kind of stuff.

They do all also share the startup for their transformation phrase, which is "Ignite Heart!", but after that it can be anything. Like... "Ignite Heart! Let's go, blazing!" or something.