Here is the Bala Tripura Sundari Gayatri mantra. This mantra should be chanted 16 times per day in order to get the desired results.
"Om Tripurasundari Vidmahey
Kaameshwaricha Dheeeemahi
Thannooo Deveeeee Prachodayaaath"
"Om Tripurasundari Vidmahey
Kaameshwaricha Dheeeemahi
Thannooo Deveeeee Prachodayaaath"