So I have been doing photography for a while, but I never really explored detailed functions (bracketing, metering, etc) until very recently even though I shoot in manual most of the time. I use to own a D5100, but it broke. After saving up a little I recently bought a used D90 and to start saving for college decided to do some freelance work. I wasn't expecting a client this quickly and am caught off by surprise because I thought I would be able to learn it by then. Up until now I never really used flash. I always bumped up the iso or any of the other settings to get the shot and since it was for myself I didn't care too much about noise and thigs like that because I loved it as a hobby. Basically I have to do a night portrait photo shoot and its outdoors. Not in city streets but out side as in park/rural/little wilderness. I ordered these 2 external flash from amazon. Amazon.com : Altura Photo I-TTL Auto-Focus Dedicated Flash for Nikon D5300 D5200 D5100 D3300 D3200 D3100 D7100 D7000 DSLR Cameras + MagicFiber Microfiber Lens Cleaning Cloth : Camera & Photo I do plan on learning more but since I dont have too much time I want to know what kind of setting should I keep my D90 on to get some good shots. I know that I need to keep the ISO low, but what about the arrangements of the flash and do I need to use pop up flash what? also what other settings I should be concerned about (metering (center or spot) ; bracketing, etc) other than f stop and shutter speed. Basically I need advice/tips on everything for night time wilderness portraits including white balance, sharpness and modes in the menu. Also I have tried looking this up but cant find a beginners guide, but is there any place where I can learn how to set up external flash and some quick tips on night time portraits. In additiong I also have an another client that wants to do a model type photoshoot with car lights. I dont know exactly how to describe it but its like the ones on calenders where the girl/s is/are posing at night on the hood of a car/s or near the car and the (main) light source is headlights. at least that's what it seems like. So I also need help/tips on this part. I feel like this one is a bit hard. The only article I have found is this but I am still missing more basic info in order to put this into action. Using Car Headlights For Portrait Photography Lighting | Popular Photography What lens will be the best one to use? I have 18-105 kit lens 35-70 f/3.3-4.5 70-210 f/4-5.6