To use STEEPVM as a writer there are a number of timeframe issues you need to address. The first one is the starting point you’re working from. If your writing science fiction your most likely starting point is today. For alternate history you need to pick the point at which history diverges and decide why. For time travel it is the point at which the travellers change the future.
The next important issue with time is the step forward you’re going to use. If your writing a day after tomorrow type story then a small step with a very few changes is the obvious choice. Maybe your just moving things forward a hundred years so four steps at twenty-five year intervals will work. If on the other hand your going forward several millennia you may want to make a giant leap forward and cover the big span in one big step or take it forward from today to a point at which something important happened and then leap forward from there to the situation your story is set in.