To say your birthday in Engpsh, you can say:

"My birthday is [month] [day], [year]."

For example:

"My birthday is January 1st, 1990."

"My birthday is July 4th, 1976."

Note: When saying the date, you can use either the ordinal form (e.g. "1st," "2nd," "3rd," etc.) or the cardinal form (e.g. "1," "2," "3," etc.). The ordinal form is more commonly used when speaking, while the cardinal form is more commonly used when writing.