Finally upgrading forum from MyBB 1.6.1 to MyBB 1.6.8!

[ALUXi33]

Finally going to upgrade my forum from MyBB 1.6.1 to MyBB 1.6.8! I know, I know why did it take me so long. Well, the guy I had in my forum that did all the upgrades is no longer with us. So I was delaying the upgrading process for the longest time now. I didn't want to have to deal with upgrading my forum and then having all sorts of trouble with my current plugins and theme.

I know it's finally time so I have some questions.

Do I download the current MyBB version first or the ones I missed?

When I upgrade are my plugins going to be the only things affected or will my "The Cure" theme as well?

Will my custom header be affected as well (see attachment)?
   

Last but not least. Is there a tutorial on how to install the latest upgrade? This is going to be my first time doing it so I really have no clue.

Here's my forum url: http://carfanaticsforum.com/index.php

[Known]

Download the latest release of MyBB, then upgrade from the version your currently using (it'll be a drop down tab under the upgrade.php page).

No, your custom header won't be effected since imported themes aren't normally touched or effected by the upgrades.

All you do is upload and overwrite ALL files with the latest MyBB release. Then you go to the /install/ directory, click on "Upgrade" and not "Install", then pick the version your upgrading from, and then it'll do the rest. After your done upgrading just delete the /install/ directory and you've completely upgraded.

[ALUXi33]

All you do is upload and overwrite ALL files with the latest MyBB release. Then you go to the /install/ directory, click on "Upgrade" and not "Install", then pick the version your upgrading from, and then it'll do the rest. After your done upgrading just delete the /install/ directory and you've completely upgraded.

Where is this done??

[Known]

via a FTP client (FileZilla, WinSCP, etc.). You upload the files where-ever your MyBB is installed at.