image · ai-image-prompting

AI Image Prompting Guide

How to write effective prompts for AI image generation models (Gemini/Nano Banana, Flux, Ideogram, DALL-E, Midjourney).


Prompt Structure

A strong image prompt follows this formula:

[Subject] + [Setting/context] + [Visual style] + [Lighting] + [Composition] + [Technical specs]

Example Prompts by Use Case

Blog hero — SaaS product:

A clean workspace with a laptop displaying a colorful analytics dashboard,
minimalist desk with a coffee cup and notebook,
bright natural window lighting from the right,
shallow depth of field, commercial photography style,
1200x630, high resolution

Social media graphic — announcement:

Abstract flowing gradient in deep purple and electric blue,
geometric shapes forming a network pattern,
dramatic rim lighting on edges,
modern tech aesthetic, clean and minimal,
1080x1080, vibrant colors

Product lifestyle shot:

A person in a modern office smiling while looking at a tablet,
showing a project management interface on screen,
warm candid photography, natural lighting,
medium shot, shallow depth of field, editorial style

Profile banner — professional:

Wide panoramic abstract background in navy blue and teal,
subtle geometric grid pattern with soft gradient,
clean corporate aesthetic, muted lighting,
1584x396, no text, space for logo overlay on left third

Directory listing — Product Hunt:

Product screenshot on a clean gradient background,
soft shadow underneath, slight 3D perspective tilt,
modern SaaS product presentation style,
1270x760, bright and professional

Style Keywords

Photorealistic

Clean/Corporate

Illustrative

Abstract/Brand

Tech/SaaS


Lighting Keywords

Term Effect Best For
Natural light Warm, organic feel Lifestyle, editorial
Studio lighting Even, controlled Product shots
Rim lighting Edge highlights, dramatic Hero images, abstract
Soft directional Gentle shadows, dimensional Blog headers
Volumetric Light rays, atmospheric Dramatic, cinematic
Flat/even No shadows, clean Icons, diagrams
Golden hour Warm orange tones Lifestyle, outdoor
High key Bright, minimal shadows Clean, corporate

Composition Keywords

Term Effect Best For
Rule of thirds Subject off-center Editorial, lifestyle
Centered Subject in middle Product shots, icons
Wide/panoramic Expansive view Banners, headers
Close-up/macro Detail focus Texture, product detail
Bird's eye/overhead Top-down view Desk setups, flat lays
Negative space Room for text overlay Blog headers, banners
Symmetrical Balanced, formal Corporate, luxury

Model-Specific Tips

Gemini Image (Google)

Flux (Black Forest Labs)

Ideogram

GPT Image (OpenAI)

Midjourney


Common Prompt Mistakes

Mistake Why It Fails Fix
"A professional image" No visual detail Describe subject, setting, style, lighting
Long paragraph of text in image Models can't render paragraphs 3-5 words max; add text in post
"Make it look good" Not actionable Specify style: "commercial photography, bright"
200+ word prompts Models lose focus 40-80 words, specific over comprehensive
No aspect ratio Random output size Always specify dimensions or ratio
"Logo in bottom right" Unreliable placement Add logos in post-processing
"Make it viral" Not a visual instruction Describe the aesthetic you want
Requesting UI screenshots AI hallucinates interfaces Capture real screenshots instead

Batch Generation Workflow

When you need multiple images with consistent style (e.g., a blog series or social campaign):

  1. Generate 3-4 test images with different style prompts
  2. Pick the winning style based on brand fit
  3. Save the exact prompt as your template
  4. Use Flux multi-reference — upload the winning image as a style reference
  5. Batch generate variations with the same style, different subjects
  6. Post-process — add text overlays, logos, crop to platform sizes

Aspect Ratios Quick Reference

Use Case Ratio Pixels Notes
Blog hero / OG image 1.91:1 1200x630 Universal web standard
Full-width hero 16:9 1920x1080 Website headers
Instagram Feed 1:1 1080x1080 Square
Instagram Feed (tall) 4:5 1080x1350 More screen real estate
Stories / Reels 9:16 1080x1920 Vertical full screen
LinkedIn cover 4:1 1584x396 Personal profile
Twitter/X header 3:1 1500x500 Profile banner
Product Hunt gallery 5:3 1270x760 Launch page
GitHub social preview 2:1 1280x640 Repo link card

Cost Optimization


Source: https://github.com/coreyhaines31/marketingskills/skills/image/references/ai-image-prompting.md · v2.0.1 · MIT License (c) 2025 Corey Haines.