(I am making the assumption that we are preparing for a short video - thirty minutes or less.  Your marketing people should be heavily involved in these steps.  If you do not have marketing people, we can take as much control over this process as you like.)

First steps - preparation

#1 - Your goal

Just what is the goal for this video?  What are you trying to achieve?  Notice, I didn't ask for a list of goals.  Your short video is like a single arrow in a quiver.  You can only hope to hit one bullseye.  If you try to hit several, you'll likely miss them all.

#2 - Who is your audience?

Sure, you want to motivate viewers, but who are your viewers?  We don't all respond the same way to a single stimulus.  Your arguments must be made with your viewers in mind.  A sales pitch tailored for business executives will likely fall flat on teenage ears.  What are your audiences concerns? 

#3 - Know your product or service

What features will be most likely to appeal to your audience.  What problems can you solve for them?  Why is your solution the one they should choose?

#4 - Outline your story

Yes, I said "story".  Like a good book, a video tells a story, but to be effective a video does more "showing" than "telling".  So as you outline your story, look for aspects that are best shown visually.

#5 - Your storyboard

Working from  your outline, create a storyboard that will become the foundation for your video production.  The term may sound intimidating, but we're just talking about breaking your outline down into scenes.  Each scene will be represented in your storyboard by boxes in two columns.  One box will have a rough sketch (even stick figures are fine) and the adjacent box will have text explaining where the scene takes place, what is happening and what is being heard.

#6 - Your script

Working from your storyboard, you can now write a script.  Keep it simple and pare it down to the essentials.  The average viewer's attention span is short and if you excede its bounds, your pitch falls on deaf ears.

Location

There's so much that goes into deciding a location for shooting your video production that we've separated this aspect into its own article.  But a few quick points -

Audio - street noise, office noise, even air conditioning  and walls can mar your sound tracks.
Interruptions - you'll need to stay focused on your production.  Phone calls and other interruptions are not conductive to efficient video production.
Outlets - studio lights can pull a lot of power.  You'll need a minimum of two separate circuits.
Availability - what if the shoot runs over the time you'd planned?  You'll need continued access to your location to avoid an extra day of shooting.

Clothing

Small patterns, stripes, plaids and red colors all play havoc with NTSC video.  Large areas of solid white or black are also to be avoided.  If you are doing a greenscreen shoot, your on-camera people must avoid wearing anything green.  Likewise, green objects should be avoided.

You can save time by asking eyeglass wearers to wear contact lenses on shooting day.  Otherwise extra care must be taken with lighting and some basic setups will have to be avoided.

If your on-screen person will be wearing a lav mic, obviously it would be best if clothing were worn that allowed the mic to be clipped properly (within twelve to eighteen inches of lips) and that will hide the usually black cable that runs to the transmitter which is usually clipped onto the waistband in the rear.

If a studio or shotgun mic will be used instead of lav mics, it will be doubly important that no street or office noise will be picked up.

Ask all on-screen people to bring a second set of clothes in a different color scheme.  If more than one person, it is best to plan wardrobe in advance of the video shoot to avoid people wearing clothing that is too much alike, etc.

Jewelry should be kept simple and not too flashy.  Large, reflective jewelry can cause issues with cameras and lighting.

If on-screen people will be doing blocking (movement), pay attention to floor type and shoe type.  For instance, leather soles can sould exceptionally loud on wooden floors.