Since I moved here last year in August.
I cycled a lot before moving to London, thought it a good habit and wanted to stick to it.
Cycling makes me arrive fully energised at work - bye bye grumpy mornings. I also enjoy not being crammed in the morning tube. And you'd be surprised how often travelling by bicycle is faster than by public transport.
I live in the North West of London, and I'd say that my cycle area is roughly bordered by the Barbican on the east side, Hampstead Heath in the north, Westminster in the south and Notting Hill in the west. But whenever Citymapper tells me I can be faster by bicycle than by public transport, and/or whenever the sun is out, I jump on my bike.
Not only to women, but to everyone: be courageous and confident. Wear a helmet. When you are completely new to cycling in London, try it in your area, gradually expand your route to less familiar roads and see if you like it. If it starts growing on you, make sure to be seen. And when it gets a bit rough: think of all the CO2 emissions and pennies you've saved, all by yourself. Good luck!
In general, I really like the friendly vibe among London cyclists. One day I was waiting at a traffic light and the man behind me offered to help out as he noticed my tyre was a bit flat (Thanks again, Mark). As we were standing on the side of the road fixing my tyre, in the timespan of two minutes two other cyclists asked if we were okay - so nice. I also lost count of the funny, tiny conversations I had with other cyclists while waiting for a green light.
My daily commute is a bit of a rollercoaster: there is no proper cycling lane on any of the roads on my route, so I'm cycling in between the cars and buses most of the time. Sometimes I enthusiastically thrive on the idea of being part of a big race, sometimes I'm utterly disappointed by how drivers can literally drive you off the road. But in the end I am always happy I chose my bicycle over a tube ride.
A bright blue Raleigh Solitaire - not ideal for longer journeys but I love it.
The fact that you at least have the idea you are contributing to a greener city, while saving money and getting some exercise.
My commute is fairly lonely, but sometimes I cycle to after work or weekend activities with a friend or a colleague.
I once attended a meeting from the Camden Cycling Campaign, which was interesting and insightful as it was a platform for sharing ideas to improve the cycling landscape in London.