First off, you need to take a screenshot of CPU-Z (CPU) and CPU-Z (Memory) - GPU-Z (I add GPU-Z sensors as well but not compulsory) and I also Add MSI AB to show my clocks and also this isn't compulsory but saves any hassle. I also add the finished score and if it was an older run, I would open it up in a webpage and shrink it to fit the screen. I have added my name to this as well, just for clarification that it is me.
To take a screen shot of your desktop, hit PrtScr once, open up paint and use the paste button. I then resize it to 1024x576 and save. That is that little bit covered.
It should look like this when done.
[spoiler]

You then need a picture of your computer to verify that you are not using extreme cooling.
It should look something like this.
[spoiler]

That is that bit covered. Now to add a submission. Head over to http://hwbot.org/team/team_mlg/#Members then click the "Submit score" button on HWbot - As I have just done a 3DMark FireStrike run, I will scroll down to where firestrike is and as I have done a normal run, I select "3Dmark" change the select menu to "Firestrike" and submit. You should be presented with a screen that requires user input and it should go like this.
[spoiler]

I filled that all in and then got another screen that required deeper user input and I tend to just add the basics (CPU/GPU/Memory/PSU) and you will need to add those desktop images again and comp pictures again/3Dmark score url (If it didn't save them) and it will look something like this.
[spoiler]

Then hit submit again and it will check everything and add your score to the bot/Team MLG/yourself.
Done.

Any questions or if anyone is unsure of anything, ask away. No excuse for not adding now and when you have done it a couple of times, it becomes very easy.