inject context and markup into another template - meteor

Question

My meteor application has the following basic layout:
<template name="layout">
{{> header}}
{{> yield}}
{{> footer}}
</template>
My header template contains a full-width header:
<template name="header">
<div>
<!--implementation of full-width header-->
<h1>{{pageTitle}}</h1>
<!--insert custom html here, e.g. search input or options (see screenshot)-->
</div>
</template>
Then, I have multiple yield templates, that's where the main content goes.
For each of my yield templates, I want to be able to load custom content "into" my header template:
set the pageTitle attribute, so I have a custom title on every routed page
insert some html content, e.g. to do show some extended options (in this example it's about filtering the result of the query, but basically it's html content)
What's the best way to do this?
For a better understanding I include a screenshot of how the page looks like:
EDIT
I came up with the following. I add another base template to the layout, let's call it headerYield:
<template name="layout">
{{> header}}
{{> headerYield}}
{{> yield}}
{{> footer}}
</template>
All the custom markup would go there, with the disadvantage, that I need 2 custom templates for each view.

Answer 1

This question isn't clear. Is the question how can I include a header template? If so then this would be the answer...
<template name="header">
<div> <!-- abosolute position full div --> </div>
<!-- markup here brah -->
</template>
Now if the question is how can I include a page title? If so then this would be the answer...
Router.route('/user', {
onAfterAction: function() {
document.title = 'page title';
}
});
This assumes you have the iron router package installed. Iron router just controls what template gets rendered when looking at particular pages. For example the route "/user" could be sent to any template that you choose. If you want information on how to install iron Router or what it can do you can see their documentation. It's necessary for meteor applications:
iron router
Update:
After looking at your profile your other questions include iron router so you have used it before. So now I am really confused as to what your question is.