I switched my entire wardrobe to androgynous clothes during the first year after accepting myself, but then when winter came in November I ended up going full-time as a product of simply not wanting to limit myself anymore. By Christmas, I was addressed in the feminine by store clerks and so on - I doubt I passed (at least on close range), but at least they figured I preferred female pronouns.
I had a few weird months of being full-time expression-wise but with a male name, and by mid January even my parents agreed it would be more practical to have a female name. So I changed it in late January.
So basically, I went full-time when my wardrobe became obviously female. Now I'll have to buy a lot of clothes for summer, and I probably will have to buy more come fall, but I prefer this over building everything before going full-time, since owning a lot of clothes I can't wear in public isn't my thing. It would simply be too frustrating.