An angel investor is likely to want to:

(a) See that you have thought about the desired profile of the other cofounder, who will complement your skills, and who you'll need to attract to the startup. Even better if you have identified a few potential candidates.

(b) A plan for you going full-time in this venture.

(c) Some kind of feedback from the potential market that you are solving a real problem, and some market sizing analysis (even if it is very rough).

At startup networking events, go prepared with a 30-60 second elevator pitch about your startup to gauge how people react to it, and who shows interest in follow-up discussions.

Happy to talk more on the phone with more details (e.g. whether it is a B2B or B2C venture), so the suggestions could become more specific.

Also, please feel free to check out some of my other answers (on my Clarity profile): e.g. what investors look for in a technical cofounder, etc.