I am also a beginner.
I tried the following method:  (there should be other better method)
http://youtu.be/jPxSG2UJEqY
1. upload photo to Flickr
2. In Flickr, view the photo and you have the option to share.
3. Click share button( an arrow icon) to obtain the html code
4. copy the whole html code to word or notepad
5. copy the part 
https://....................jpg
6. In HKBWS, start a new thread and click the image icon (the right hand side of email icon)
7. A long box appeared and paste the  
https://.................jpg
8. 

 appeared on your messge
9. DONE ( hope it works) 
BTW, is there any Saunders’s Gull        黑嘴鷗 in the above photo?
THX!
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 Last edited by derekhon2 at 28/02/2015 22:39 ]