I tend to follow some prominent people in the programming languages / frameworks I'm interested in, which is mainly Rails and Elixir / Phoenix things. As I've gotten more interested in DevOps type things I've found people in that space also. And then some prominent VCs and other random people in tech I've come across.
The interesting thing is that the 'X Person liked this' feature that injects tweets of people you don't follow into your timeline actually works wonders for finding more people in tech to follow. I've stumbled into following people with very different backgrounds / viewpoints as myself to be more informed of the greater scope of the tech world.
A list of some of the people: https://twitter.com/mipsytipsy https://twitter.com/IanColdwater https://twitter.com/martinfowler https://twitter.com/wycats https://twitter.com/polotek https://twitter.com/ChrisKeathley https://twitter.com/samsaffron https://twitter.com/vsupalov https://twitter.com/nateberkopec https://twitter.com/redrapids https://twitter.com/keystonelemur https://twitter.com/kelseyhightower https://twitter.com/pragdave https://twitter.com/jessfraz https://twitter.com/searls https://twitter.com/wbruce https://twitter.com/ChrisGSeaton https://twitter.com/eileencodes https://twitter.com/sasajuric https://twitter.com/dhh https://twitter.com/josevalim https://twitter.com/chris_mccord https://twitter.com/benedictevans https://twitter.com/tenderlove https://twitter.com/pmarca https://twitter.com/davemcclure https://twitter.com/bhorowitz