Why did you become a soferet and when did you become a soferet?
Why: it seemed like a good idea. It relates to being simultaneously good at mathematics and crafts, because sofrut is a combination of calligraphy and dense talmudic reasoning. Arts and crafts were a hobby while I was taking mathematics at school and university.* I never really knew what I wanted to do with myself, career-wise;** I thought something which combined analytical reasoning with craftsmanship would be nice, but I didn't know what that might be.*** I figured that when the right job came along, I'd know about it.
A chance combination of happy circumstances at college got me interested in Jewish law, and rigorous mathematical training is a jolly good foundation for relentlessly convoluted Talmudic reasoning. I was doing a good deal of calligraphy in college, chiefly because calligraphy materials travel easily, and another chance combination of happy circumstances introduced me to Mordechai Pinchas and the concept of the ritual scribe. Whereupon I realised: here is a job which combines a lot of theory with a lot of craftsmanship, and is incidentally a glorious combination of ancient and modern; this could be something I could be very good at.**** The right job had come along, and I knew about it.
When: On the whole, "Purim 2004" is the simplest answer, but asking "When did you become a sofer" is sort of like asking "When did you become a journalist?" There isn't a clear starting point. A rabbi is different - before ordination one is not a rabbi, after ordination one is. But when does one become a journalist? First article? First paid article? First byline? First month living on income from writing alone? Same with being a sofer - there are a number of landmarks, but no one defining moment. One's first Megillah of Esther is a landmark. Or the first time a respectable authority says your knowledge is sufficient and your work is kosher. Or the first time a congregation puts its trust in your work, using your scroll to fulfil their obligations. These all happened to me in early 2004. Sofrut was my main source of income by early 2006. One tradition says you are only truly a sofer when you complete your first Torah scroll; I haven't done that yet, but stay tuned.
* I took art in secondary school, but the teacher liked people who did giant nudes, which I was far too embarrassed to attempt, so I drifted towards the sciences, where you could get high marks without having to deal with naked bodies.
** okay, there was a long period where I wanted to be an actor, but let's not go there
*** I got sent on loads of "Women in Engineering" courses, designed to entice women into being engineers; I never realised there was more to engineering than competing to see who could build the strongest bridge. Competitions and bridges between them completely turned me off.
**** Sometimes I feel like I ought to apologise for being so pragmatic: choosing this work because it combines things I'm very good at and things I enjoy very much, not because of any spiritual imperatives, like other women seem to have - visions of writing a Torah scroll, being inspired by the holy letters, that sort of thing.