Schedule proofing and copy editing in your project timeline before it goes to print.
If possible, copy and paste text into a Word document. Right away it'll point out obvious typos and misspellings. If you don't have that luxury, it just means it will take you a little longer. Begin proofing the client-approved layout, and then read it in its entirety. Don't get distracted by the ink color, design or if anything is not centered.
Now re-read the copy looking at each word individually for spelling errors. If you find mistakes, use a red pen and mark or correct the layout.
Read the text backward, word by word, starting at the bottom right. Read aloud each word concentrating only on the spelling as it is written. Saying each word out loud helps find mistakes and it pays off big time when you catch it early.
Now double-check spellings of names and addresses, including envelopes. Read addresses backward as well, paying close attention to numbers.
Schedule an hour to research menu items online to check the spelling, and pay close attention to accent marks.
Allow 1-2 hours
Programs contain a lot of names, or event dates, or both, so grab the client-approved copy, a red pen, and open a search engine.
Check the spelling of names letter-by-letter. It could be Lindsey or Lindsay or Lynzee or Lin-Z. If the program includes celebrities or VIPs of large corporations, search them online for correct spellings. Is it Renee Zellweger or Renee Zellwegger? Is it Katherine Hepburn or Katharine Hepburn? Google it, just in case.
Use a calendar and make sure the days and dates match. Again, even though the client approved the copy, it'll pay off to double-check the day/date. If you don't, you'll still have to re-run it, and probably at the last minute, leaving little time to properly proof. Time is money. Just make sure to let your client know you found a mistake and ask permission to correct it. You'll be a (s)hero in the client's eyes, and you're almost guaranteed to get her next project.
If you wrote the copy yourself, it's advisable to have someone else read it. Make sure you ask her/him/them to carefully read all the words.
Proofreading takes time, and there are no shortcuts to finding mistakes. Here's a good example of a casual invite mistake:
Please join us for sips and bites to celebrate the engagement of Lisa and Clarke.
Festivities start at 6 o'cock, Friday, August 3, 2018
Given with love at the home of Rick and Morty
331 Guadalupe Street
Did you catch the typo? If not, start at the bottom, read backward, and say each individual word aloud, exactly how it's spelled. And there it is. This is an example of what can be easily overlooked. Be vigilant about your proofing, and don't rush the process.