Skip the line at Shake Shack at Nats Park and bring your own burgers from across the street. (Tim Carman/The Washington Post)

Opening Day at Nationals Park on Monday was, in a word, painful. It was hard on your feet as you stood in line. On your patience as you stood in line. And on your ability to enjoy the Nats's victory as you stood in line.

The line score for the first home game of the season: Lines 1, Fans, 0. The fans did not take the loss well.

The Nationals issued a statement that was, if not a formal apology, at least an acknowledgement that the owners need to improve the ballpark experience before Wednesday night's game with the Marlins. Let's hope they do, but whether they do or don't, I have some suggestions on how to improve your concessions experience, based on my own Opening Day visit to Nationals Park.

Bring cash. I know, no one carries foldable money anymore. But given the troubles on Monday, with ATMs and credit card machines going down, I'd recommend slipping several Jacksons in your wallet. Few things at the ballpark are worse than reaching the front of a concessions line, only to learn your plastic's no good. Which reminds me: C'mon, Nats, put some signs up to announce the stand is cash-only for the day!

A side note: Season ticket holders, whether they have a full or partial season plan, can skip the line at more than 30 stands at Nats Park. One benefit of being a "plan holder" is that the Nats issue you an eCash card, which allows you to stand in a separate, often far-shorter line from the poor fans who can afford only an occasional game. It's like the priority check-in lane at airports, only for hot dogs.

Visit Shake Shack before the game. You may not know it, but you can bring your own grub to the ballpark as long as you follow the team's guidelines, which allow food "contained in single serving bags within a soft-sided container or cooler that does not exceed 16" x 16" x 8"." This is a tender mercy to those folks standing in the long, serpentine line at Shake Shack on the club level, watching inning after inning roll by on nearby monitors. The burger chain with the cultlike following has just opened a new location at 54 M St. SE, only a block from Nats Park.

You get the drift here, right? Stop by the M Street Shake Shack before the game, place your order inside a Nats-appropriate cooler or container and enjoy the entire ball game with your ShackBurger. But be patient: I stopped at the new location on Monday, and it was barely controlled chaos in there, despite the lack of customers. The shop is clearly still getting its systems in place.

The Chesapeake Bay tots from See. You. Tater. at Nationals Park. (Tim Carman/The Washington Post)

Try the See. You. Tater. stand. The new stand, a pun on MASN play-by-play announcer Bob Carpenter's home-run catch phrase, far surpassed my expectations, which, I must confess, were pretty low. The concessionaire offers both chicken wings and tater-tot bowls for your game-time consumption.

If you want wings, skip the ones here and instead visit the Bonchon location on Half Street SE before the game. Then follow the same protocol as you would for bringing those ShackBurgers to the ballpark.

I tried a couple of tater-tot bowls, which come across as poutine with ambitions. (Each bowl is a whopping $12.) My favorite was the "Chesapeake Bay tots," which I immediately dubbed Ches-Mex tots. It's a bucket of tots smothered in "crab queso" and topped with a roasted-corn-and-poblano salsa and queso fresco. In bars, tots are finger food. In this preparation, they almost demand a plastic fork. So don't forget to pick one up before heading back to your seat. You won't want to miss a single bite.

Be flexible. On opening day, a colleague and I visited two stands that did not have items advertised on their menu. The Change-Up Chicken stand did not have its new Thai chicken skewers over jasmine rice, and the Virginia Country Kitchen cart didn't have its chicken-fried-steak-and-half-smoke biscuit. I was bummed that the Franken-wich had gone AWOL: I wanted to find out if Texas and the District could finally work together, at least when tucked inside a biscuit.

A worker at Virginia Country Kitchen told me the ingredients for the new biscuit sandwich never arrived on Monday. I heard that at least one other stand didn't receive its supplies either. This kink in the supply chain may or may not be an aberration. Regardless, if you're going to stand in line for a particular dish, either ask first if it's available or have a back-up option ready when you hit the register.

Also remember: If the Change-Up Chicken stand near Section 110 is too crowded, check out the other location at Section 130. A number of stands have multiple units, including Ben's Chili Bowl, District Drafts, Dolci Gelati, Virginia Country Kitchen and others.

Check out the guest beers. Among the new offerings this year, Nats Park has introduced a rotating "guest tap" series during homestands. The series lets local craft breweries take over a tap handle at two District Drafts carts, one on the main concourse and one on the upper concourse. Fair Winds Brewing is first up for the Marlins series. On Opening Day, the Lorton, Va., brewery offered its Howling Gale, a West Coast-style IPA that "explodes with tropical and citrus notes," according to the description at the District Drafts cart. The District's Right Proper Brewing will take over the taps during the homestand with the Cardinals, starting on April 10.

Finally, don't forget that Devils Backbone, the Virginia-based craft brewery owned by Anheuser-Busch, has created an exclusive beer for Nationals Park this season: Earned Run Ale, or ERA, is only available at the new Devils Backbone bar near Section 301. Post beer columnist Fritz Hahn says ERA "is a bright, quaffable golden ale, with a burst of lemon and grapefruit from Amarillo and Centennial hops, and a pleasant bitterness."

I say I'll have one of those next time I'm at Nats Park.

Read more:

What’s new around Nationals Park in 2017? Beer gardens, brewpubs and Shake Shack.

New at Nats Park: A tots and wings stand, ice cream push-pops and more beer

Beer of the Week: Earned Run Ale is a Nats Park exclusive

Battle of the ballpark belly-busters: Nationals Park vs. Camden Yards