.
If you're already interested in some particular issue, then that's also a nice way to get started.
Please be aware that contributing to V8 tends to have a rather long and steep ramp-up curve, because it's a large and complex codebase. The first couple of weeks of working on it probably won't feel very productive. If you were hoping for the occasional week-end/free-time contribution, you may have more fun with a smaller/simpler project.