Shooting people in low lighting without flash

[christyloveslamp]

Hi, I'm a new new NEW photographer with literally NO experience. I have a good eye for what'd make a good picture, and the creative energy to get really cool portrait setups, but absolutely no know-how. I'm interested in doing relatively low-lit shoots of my friend (see examples taken by other photographers below) but I don't know what settings to use. PLEASE help!!!! And any other tips for shooting people in a nature setting (or heck in general) would be amazing! PS-she's heavy set, not 'fat' or anything, just the heavier side of normal, and she's incredibly self-conscious about the shoot. Is there anything in specific that she should/should not wear (I know basic fashion rules, but I also know that some things just look AWFUL on camera), or any angles I should/shouldn't shoot from, or anything else to take into consideration?? Thank you sooooooo much!