Use the phrase "I don't claim..." to let listeners know that you don't have too high of an opinion of yourself:

I don't claim to have all the answers.

I don't claim to be the best cook.

I don't claim to be an expert.

People often say "I don't claim (something), but..." before sharing their advice or opinion:

I don't claim to be an expert fisherman, but I'm pretty sure that that's not how you're supposed to do it.