Here's some sample microcopy for a submission form:

Title/Subject Line: Submit Your Content

Headline: Share Your Ideas with Us

Body:
We want to hear what you have to say! Share your thoughts, insights and creative content with us by submitting it below. We welcome all types of content: articles, photos, videos, podcasts, and more. Please include as much detail as possible so we can feature your content accurately. Don't be shy - we're excited to see what you'll share with us!