TPG’s Points and Miles team has been writing weekly posts in its new Quick Points series. This series aims to help you earn points, redeem miles and maximize your travel with bite-sized and to-the-points posts.In today’s Quick Points post, I’m walking through how adding one Google Chrome plug-in helps me earn thousands of extra American Express Membership Rewards points each month with the click of a button.Get the latest points, miles and travel news by signing up for TPG’s free daily newsletter.At TPG, we talk a lot about online shopping portals. They are a great way to double-dip on rewards when you shop online. You can use aggregator sites such as Cashback Monitor to see which airline, credit card and cash-back portals are offering the best deals for certain sites — but those extra steps are easy to forget and can deter people from taking advantage of them as often as they’d like.Personally, I end up forgetting to go through Cashback Monitor more times than not when I’m in a rush to buy something, or when I click through an ad or article to make a purchase. That’s when my favorite plug-in comes in handy.Rakuten is a cash-back shopping portal that has a Chrome plug-in to help simplify the process when you shop. Basically, you earn points without thinking about it.When I’m scrolling through a site that offers a bonus through Rakuten, a small notification pops up in the corner of my screen. I can click that notification to automatically move over to the shopping portal — it doesn’t take me to a shopping portal homepage or the website’s homepage, so there’s no interruption to my shopping flow.I have Rakuten set to earn Amex Membership Rewards instead of cash back, too. So every time I click on the pop-up reminding me to go through a portal link, I’m earning valuable Membership Rewards points (which TPG values at 2 cents each).While Rakuten isn’t available on every website and other portals may have higher bonuses, I love that the plug-in makes the process of using a shopping portal to earn extra points seamless. If it takes me too many extra steps, I’m less likely to go through the process when I’m in a rush — Rakuten saves me time while making my purchases work for me.Sign up for our daily newsletterEmail addressSign upI would like to subscribe to The Points Guy newsletters and special email promotions. The Points Guy will not share or sell your email. See privacy policy.How to earn Membership Rewards with RakutenSetting up the plug-in is easy. Here’s a step-by-step tutorial:Step 1: Sign up for an account(Screenshot courtesy of Rakuten)Head to Rakuten.com and sign up for an account. You can sign up with your email, a Google account, Facebook or Apple. Right now, you’ll get a $30 cash bonus if you sign-up and make a $30+ purchase within 90 days.Step 2: Go to settings and switch to Membership RewardsOnce you’re logged in, go to “Account Settings.” It’s located in the upper right-hand corner of the screen under the drop-down menu next to your name and current balance.From there, you can manage your account settings — login credentials, linked accounts and how you’d like to get paid. Options include PayPal deposit, “Big Fat Check” and American Express Membership Rewards. Go through the process of linking those accounts, and you’ll be set to earn Amex points rather than cash back.(Screenshot courtesy of Rakuten)Step 3: Add the plug-in to your browserAfter you get all set up to earn Membership Rewards, add the plug-in to your browser. Head to rakuten.com/button.htm to add it to Chrome.Step 4: Use it when you’re shoppingUsing the plug-in is easy. Anytime you’re shopping on a site that earns rewards through Rakuten, a small pop-up will appear in the upper right-hand corner of the screen. Click on the pop-up, and it’ll do all the work for you. Once your rewards are activated, the pop-up will turn purple in confirmation before disappearing as you resume shopping.(Screenshot courtesy of Aerie and Rakuten)Rakuten tracks your entire “shopping trip” with a certain site, so you won’t have to reenter the portal as you scroll through the site and add things to your cart.The plug-in is an easy (and free) way to rack up extra points on your online purchases with just the click of a button … literally.