Blogging Etiquette

So I have only been doing this blogging lark for a few months and I'm still not 100% sure I'm doing it right or if there is even a right or wrong way. I basically just document my daily life throughout my journey to lose weight and get fit. I have added Instagram and twitter to my page but bear with me, I'm just as clueless about these things as I am blogging!

If anyone can steer me in the right direction with these things, I'd be grateful

Twitter - So is this basically where I update my day, several times a day, in a short sentence? like "just had a yummy lunch of blah blah blah" and then comment on other people's Tweets?

Instagram - Here is where I am supposed to take photos of said yummy lunch, kids in the park, my outfit etc and share them with a caption - am I getting this right?

Pinterest - This one I just spend ages trailing through and pinning what I like to my boards. So if you follow me I suppose the idea is that if I pin something you like, we may have a common interest and I may pin more that you like?

There should also be a rules of blogging bible or something, I had no idea if someone comments on your blog you are meant to go over to their blog and comment too. I also seem to be following and linking up with a lot of overseas bloggers. I take it this is ok. It just means I may not be able to meet at certain events or get togethers. I just follow the people I have most in common with and there don't seem to be many of my kind of blogs in the UK. If you know of any, feel free to let me know, although I thought the whole point of blogging (other than to document your life) was to make friends that you wouldn't normally due to meeting people from every part of the world.

And in between all this and my personal facebook account, writing this bog and stalking reading other peoples blogs, I am supposed to have a life?

I had no idea a little on line journaling could be so much work!