Do you have any strong feelings about things you would like to - or wouldn't?
Take that down to the task level. Obviously any job will have a certain amount of admin and paperwork, but would you prefer a job with a lot of admin, or less? What about speaking on the phone? Speaking with customers? Do you want a practical, active sort of job, or desk-based?
Do you prefer set hours, or could you consider shift work or other irregular hours?
Would you rather be based in one office, or to travel around? Do you have a car or are you reliant on public transport?
What is the minimum income you need? Does that change if other variables like travel or childcare costs would increase?
Along with your existing qualifications and skills and experience, these sorts of questions and more will help you form a profile of your ideal job. You need to know what your personal redlines are, be it around hours, pay, travel or whatever - it also helps to work out where you feel more flexible - a longer commute may be acceptable for a significant wage increase, for example.
If you're a member of a union, check whether they offer any careers counselling - mine does. I still had to pay, but it was a reduced rate.
You can get adult careers guidance - there are a ton of sites online, as well as books like What Colour is My Parachute? but essentially, they can only work with you doing the work of thinking about your preferences and so on. However, once you've done that, there could be some use if it offers ideas you wouldn't have thought about - I suspect many of us don't consider particular careers because we don't really have an understanding of what the work would really involve and therefore if it would suit us.
You'll also be able to find a ton of info on job applications and CVs and so on, but again, you still need to do the work on your qualifications and experience that should be added.
Good luck!