Om bhu-bhurva sva tat-savitur-varenya
bhargo devsya dhimahi
diyo yo na prachodayat ॥
Meaning
You the eternal one, the physical one, the source of life
oh adorable Sun God the brightest of all, clean my soul and purify me
enlighten me, inspire me and lead me to the right path of life
You can recite Gayatri Mantra three times in a day. It is best recommended to recite it early in the morning, in the afternoon and in the evening just before the sunset.