To post image you have to download your image from coinigy on your computer.
Then go on http://postimg.org then upload the image. Get the png extension named as direct link.
Then come to steemit and post this code: ![](Your png code from postimg)
And you will see your image uploaded on Steemit.
Cheers!
Thanks a lot @cryptotradings ! Will try that out on my next chart.