Get creative with emojis in email subject lines to increase open rates! Generating witty text... A mobile-responsive email can increase clicks by 15%. Always check mobile previews before sending out emails. Don’t forget to add a fun, relevant call-to-action button to your email. Boost your email opens with a punchy subject line. Don’t forget to add a short preview description to encourage people to click on your email. Sit up straight. Keep your email subject line short and attention-grabbing.