Interesting tips! Congrats to the OP on getting your tickets booked!
Can anyone explain how the companion pass on SW works?
If you earn 110,000 Companion Pass eligible points with Southwest within a calendar year (Jan 1 to Dec 31), SW will issue you a Companion Pass. The CP is good for the current calendar year, and the next. (Example: If you earn CP now, you'll have it through December 31, 2017).
Anytime the CP earner books a flight, whether they paid with cash or with points, they can use their CP to book a flight for their companion to fly for free. As long as their is any seat available on the plane, the companion can be booked. The companion will just pay the mandatory 9/11 Security Fee, which I believe is $5.60/one way.
You can change who is designated as your companion up to three times per calendar year.
The easiest way to earn the qualifying points is to sign up for two of Southwest's Chase Visas. There are three available: Personal Plus, Personal Premier, and Business Premier. Although the general public offer on Southwest's website is much less (I believe it's currently 25k points), there are ways to get a 50k sign-up bonus with all three cards. Each card has a minimum spend of $2,000 within 3 months of opening.
If you sign up for two Southwest cards and complete the minimum spend, you'll already have 104,000 points (50k sign-up bonus + 50k sign-up bonus + 4,000 points for meeting the minimum spend on both cards). You'll only be 6,000 points away from the CP, and there are many ways to get that last 6,000. Additionally, when you earn the CP, you don't trade your 110,000 points for it. You'll keep your points.