You can use an external image server, or I just use the forum's internal image server:
http://fivearts.org/fileserverWith this server, here are the steps to upload an image:
1. Log in with your username and password
2. Click <Upload>
3. Copy an image and paste it
4. Click <Upload> and then check if the image needs to be edited or not
5. Scroll down to click on <Embed Codes>
6. Scroll down to
Full Image - BBCode7. <Copy> the BBCode and paste this code into your forum post. You will notice a in your post
It may look a bit cumbersome at first, but then all these steps can be done very quickly on a computer (not mobile).
For example, Tientai used this method to insert the hexagram image in your divination in
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