HOW TO DETERMINE A TURTLES GENDER? IM CONFUSED...HELP ME PLEASE.?

i have this baby singaporean turtle, it is very active and keeps on popping its head out. yeah, so its very smal, like the size yur pinky(lil smaler than that ai gues). its hard telling the gender coz its all mixed up. ive gone thru many articles that say abt their characteristics but im confused. nami(turtle's name) has a long tail but its not very fat. its not old enuf so i cant judge nami by its claws. nami's bottom is flat. eyes are blackish brown i gues. outer shel is round and curved. i cant realy find the cloacal hole and i dont want to flip nami over coz its dangerous. oh and btw, just so make sure, it has red lines on her neck and a leaf green shel(just so u no wat kind of a turtle im tokin bout). i wish i cud post a pic but im askin this thru ma cel. thats about it. thank you fr helpin me. :)