As someone who likes to share his ideas, I find that writing them is a great way of doing so. This is one of the reasons I enjoy blogging - I can share my ideas pretty easily (and searchable, too!). Although I have blogging in mind when writing this, it can extend to other formats of my writing, as well. One method I have found that works best for me in getting my ideas from my brain to the Internet/blog post begins, paradoxically enough, by avoiding the computer screen. I first write out my ideas, whether it be with pen and paper or with dry erase markers on a white board, etc. and I am able to get a bird's eye view of what I want to get out.
Then, I might type it up on my tablet or on my computer.
However, rather than taking it directly to the blogging platform webpage, I frequently take it to something simple - e.g. Google Drive - to type it up. I think this might have to do with a fear of screwing up or some sort of perfectionist strain in me that makes me reticent to type up content straight into the blogging platform. From there, I will, however, then copy-and-paste the written/typed content into the blogging platform. Then, of course, I can worry about adding in any pictures into the post.
Another method I have found that works for me is to type in notes on my cell phone on Google Drive (or it could be Evernote, etc.) while out and about.
That way, I can then add in further content while with my tablet (when wi-fi connected) or computer (wi-fi, of course). Then, I can copy-and-paste that content (or outline of content) into the blogging platform.
I readily acknowledge the lack of efficiency that goes into these methods; however, when staring at a computer screen with whatever I need to write in front of me (blog post, article, etc.), it appears to me to be quite a daunting task. But, when the stakes are much lower and I can easily add in content to something like Google Drive or even a simple text/note app, I have no fear about what I compose there and I know that it is easy to edit it down at the next step :)