I assume you already have a 3speak account, but if not go to 3speak.tv and sign up with your email, then go to your studio and add your Hive account to it.
Then you just use the upload in your 3speak studio, add all detaila and your video and upload it.
Before uploading you should edit your video first, I use the YouCut app whichbis fantastic for this and the free version does not leave a watermark, I am upgraded though.
So cut your video together as you want it and then save it, and here is where you can save a lot of data in the upload as you can set the Resolution, Frame Rate and Quality, a 5 minute video can be saved with good enough quality that it takes less than 100 MB in size.
For the header graphic use Canva or Desygner, and include it for a few seconds at the start of your video too.
That is some tips.
!ALIVE