How do you make meringues?
As you have not posted a recipe I can't tell you how to fix it for next time. I can't tell you what is wrong with them though.

Brown, because the oven was too hot. I do mine by blasting in oven at 135c for 15min then turning it off and going home. Then when I get back to work in the morning they are perfect.

Flat, because... Many possibilities


Over/undrr whisked eggs
Too much/little sugar
Too much moisture
Time between whisking eggs and getting them in the oven was too long (5min maximum)
Fat has got into the mix. Possibly from a dirty bowl/whisk/bit of egg yolk or even your hands. 


To help control the whisking of eggs I mix about 1 part corn flour with my sugar. And an equal amount of white wine vinegar. So whisk your eggs up to stiff peaks, tip in your sugar/cornflour mix whisk a little till it starts to dissolve then add the vinegar. Keep whisking until all the sugar has dissolved and the mixture is really shiney (rub a little between your fingers if it feels grainy keep whisking).

As soon as it's whisked (use the old trick of holding the bowl upside down if it stays you should be fine) get it straight on a baking tray however you want and into the oven. This part is critical the longer it sits UN cooked the more likely you'll have a disaster.