Lazy Girl Photo Editing
Once you've got your image, crop it to make the most of the composition. You will see all your editing tools down the left hand side. Everything you need to edit the colour, crop and tones is going to be in the 'basic edits' bit.
In low light, you can often find that you image will boarder towards a yellow tone. To edit this, just click on 'colours' and choose the neutral picker. Take the little dropper and click on any part of the image which is white, grey or black and it will adjust the tone accordingly. I always go for the lightest grey part of the image and this seems to work most of the time. If you click in the wrong place, just click again to correct it until you get a crisp white!