Your message should be entirely unique, honoring the individual, their hard work and their accomplishment. Begin the message with heartfelt congratulations for both the achievement and all the work that went into it. Add a personal touch by sharing how you feel about the recipient or how you've helped out along the way. Next, send well-wishes for their life going forward, marking the next chapter with sincerity and heart. Adding jokes, photos, stickers or personalized gifts further ups the ante.