An excellent birthday toast for an 80-year-old focuses on the relationship that exists between two people and showcases that relationship through nostalgia, sincerity and humor. There are many strategies to make a memorable speech:
Reference the relationship and milestones: Talk about shared experiences, especially those that focus on the relationship. Be sentimental, and throw in a fun story. Stories that highlight the senior's wisdom and accomplishments are usually a hit.
Crack a joke: Nearly every "how to give a speech" guide mentions telling a joke. It makes the toaster more comfortable with the audience and vice versa, and it ensures everyone enjoys the toast. Be sure to keep it clean.
Keep it short: Stories and jokes are great devices, but the toaster should not get carried away. Short and punchy is always better than rambling and long-winded.
Use a quote: Using a famous quote or two adds either humor or emotional depth to a toast, depending on the context.