How would i ask this girl out?

Today I was at a car boot sale and i saw a girl i felt extremely attracted to.I think she was indian or muslim, and she had on a very bright sari(?),she was with a couple of friends or could have been sisters or relatives, i wanted to tell her how beautiful she was and i would have loved to have taken her out and treated her like a princess.I am white english and must be good looking as i do recieve a lot of glances from the ladies.I went back to look for her as i probably would have complimented her.How would I have done this to a girl outside of my culture? is it a good idea to do compliment her infront of her family? what should i say? do indian/muslim girls date white english men? could i get some information preferably from indian/muslim women on how best to act in this situation should i ever bump into her or meet anyone like her again.Thankyou :) x