Hi,
Go to https://postimages.org/, then click on Choose Images. In the newly open windows, Browse to your image and click "Open". After that you will see "Direct Link" to your image. Just copy it and paste into the "Image URL" box in the Add post page.
Keep the image family friendly hehe.
There are some suggestions in the faq I believe, as long as the host isn't spamming, and you can link directly to the photo, you should be okay. I typically link my deviantart photos directly all the time.