In addition to the excellent advice below I would add 2 points. Firstly, many people who want to become lecturers accept that this is a longer term aim and take whatever relevant jobs they can until they are succesful in an academic job application. For example, the social sciences really lend themselves to jobs with think tanks (e.g. IPPR), public sector bodies with a research component (e.g. the National Audit Office) and charities. It is perfectly possible to keep publishing while working outside of academia and to use this experience to get a lecturing job later down the line.

Secondly, although it's not directly related to your question, and people may immediately argue that I'm wrong, it might be wise not to expect that a PhD which begins immediately after your bachelors degree will be done and dusted in 3 years. There is a good reason many funding bodies expect a masters degree, mainly being that students have a chance to improve their research skills, begin exploratory work on a topic and get experience of writing longer dissertations. If you are put off by the idea of taking longer than three years from the end of your first degree, then this might be something to bear in mind.

Hope this helps!