Examples of 90th birthday toasts are available at BirthdayMessages.net and SpecialSpeeches.com. Both sites contain messages that celebrate the birthday with various sentiments in the form of poems, quotes and toasts.
BirthdayMessages.net provides wishes, quotes, poems and toasts for many occasions. Its birthday toasts include funny, inspirational, romantic, clever and sentimental messages. One clever birthday toast provided is "May you always dance as if everyone were dancing with you, sing in a chorus of thousands and live each day as if it were your first, full of joy, wonder and blissful innocence. Happy birthday!"
SpecialSpeeches.com suggests that a 90th birthday toast should offer respect, love and appreciation for the person being honored. It provides tips for the celebration theme and timing, ideas for getting others involved, and a selection of birthday toasts for seniors, including Mark Twain's "Wrinkles should merely indicate where smiles have been."