Yes, new topic is the way to go when you post a question. Welcome from the UK!
To bring the bottom thread up, let the needle down through the fabric and bring it back up. (If your machine has a needle-down button, use that. If not, you might want to use the hand wheel rather than the foot pedal, to make sure you're only doing a single needle-down-and-up. If you do more, you can't pull the thread up anymore.)
Then gently tug on the tail end (the loose dangling end) of the needle thread. You may need to hold the other end of the needle thread, near where it goes into the needle, to make sure it doesn't pull through.
This brings up a small loop from underneath the fabric. tug on that and you should get your bobbin thread end.
Clear as mud? :D