You will see many photographers with flash lights to illuminate subjects. I prefer to use the light that we already have, the sun!
In my previous post I spoke about the golden hour (take a look here). This is the best kind of natural light.
If you can't get out first thing in the morning then try and get out before the midday sun hits as this can create harsh shadows. If you do have to shoot in the harsh sunlight of midday, try not to shoot direct into the sun.
But one thing that I would suggest you go and buy is a reflector. If you are working on you own then a small reflector with a handle that you can use on your own is probably best.
Choose the colours of the reflector that work best for you. Luckily most come with covers so you can change them.
There are many different ways to use your reflector all dependant on the subject, time of day etc. You need to go out, find a subject and play around. If you are photographing people please do not shine the silver/gold side directly into their eyes.
Go out and practice with your reflector let me see your results.