How to add sidebars on tumblr?

[Madia]

Ok, so basically I have a tumblr. I'm new to it and i want to know how you add those sidebars. You know, in accounts when you click on them theres this thing on the side for ex;

ask
archive
twitter
etc

i know how to enable the ask, but what about the rest? like if you connect it with twitter it sends a link, it doesnt directly link you to it.

i heard you go to edit HTML then ctrl+f then type image:sidebar but thats not there.
Help would be appreciated
my tumblr: toxichaven.tumblr.com

thanks xx
p.s my theme is Fluid Neue. it like has a sidebar but just ask wanna know how to add other stuff ex this girl has one and when you click it it has like a scratch on it something nice and cool please help thanks x