If you are not automatically signed in when you go to http://www.betterinvesting.org, make sure to click the Member Login button, then fill in your login and password.
Once you are signed in, click the blue Store tab located near the top of the page. If you are signed in, it will be the first tab on the left. From the store page, click Online Tools, along the left hand side. The SSGPlus upgrade is listed as Plus Upgrade - includes the new SSGPlus App. Below the details of the Plus Upgrade will be a drop-down menu showing subscription options. There are four options; depending on if you are currently a member of BetterInvesting as an individual, or through a club, and if you would like to subscribe for a year, or a month at a time. Choose the option you would like, and then click Add to cart to continue with the purchase.