Journaling is a great plan.
I don't know if you use this in your journal but part of CBT is learning to notice and then challenge unhelpful thoughts - in CBT jargon these are called Negative Automatic thoughts (NATs).
Here is a real example, from the woman with GAD who I mentioned above.
In one group session she said that she had been invited to do a harbour cruise.
Her GAD kicked in with a NAT; "
There might be a big storm on the harbour. The boat would sink and I can't swim.". In CBT jargon this is called catastrophising.
We helped her to challenge this NAT in Q&A format.
Q: What is the weather forecast for the day of the trip?
A: Fine with light breezes.
Q: is the boat old or new?
A: New.
Q: Who will be running the cruise?
A: Experienced professional sailors.
These and others helped her to challenge her NAT. She did the cruise and had a great time

.
CBT in action.