Regular expressions can be intimidating at first, but with practice, you'll become proficient in no time. Just remember, regex vs. hobbies is a losing game.
Start with the basics: ^ for start of string, $ for end of string, and \d+ for one or more digits.
Next, practice with some regex tournaments to test your skills.
Don't get discouraged if you fail; regex mastery takes time. Even the great Regex Wizard of Oz had to start somewhere.
For more regex tips, visit our regex for the clueless subpage.