After my first overnight Amtrak trip, I learned that the train line has a loyalty program that rewards passengers two points for every $1 spent. Points may be used for tickets, hotels, shopping, and dining, and it's free to join.

If I'd signed up, I would have earned 3,000 points toward my next Amtrak adventure. I missed out that time, but I recently joined the program following my Denver to Salt Lake City journey.

When I booked my first overnight Amtrak ride, I didn't check if my ticket included access to the Metropolitan Lounge at NYC's Penn Station, where I departed.

The Metropolitan Lounge is a quiet waiting area that's free for Amtrak customers in first-class and sleeper cabins. It has comfortable seats and free snacks and drinks.

Since I didn't realize my ticket included access to the lounge, I waited in the seating area for all passengers and was less comfortable than I could have been.

That first ride taught me that overnight trains are very bumpy, and I felt sick for most of it.

For all my overnight rides since, I haven't forgotten to pack my medicine.

I chose to sleep in the top bunk on my first overnight train. I thought it would be more fun, but it made the ride feel even bumpier.

On every overnight ride since, I've opted for the bottom bunk over the top and have found that I sleep better that way.

Amtrak sleeper trains have a variety of accommodations, from regular seats to private rooms.

I traveled from NYC to Miami in a $500 roomette, a 20-square-foot enclosed private space with a foldout table, two chairs that fold out into beds, and an additional bed that pulls down from the ceiling.

On my way back to NYC, I spent 30 hours in the next level up, a bedroom accommodation. It cost $1,000 for twice as much space as the roomette, with a private bathroom.

After these rides, I thought the roomette felt cramped and realized that spending twice as much money for double the space in the bedroom was worth it.

Some of the sleeper trains I've taken in Europe did not have private accommodations like Amtrak. Instead, they had shared cabins, and I learned that some were more comfortable than others.

For example, two Nightjet routes I booked offered regular assigned seats in enclosed seating carriages of six or shared sleeper cars with bunks of four or six. I tried both.

For my ride from Berlin to Vienna, I booked a $40 regular seat inside a seating carriage with six seats facing each other.

The seats didn't recline enough to be fully flat, and the small space felt like a tight squeeze for six people with limited legroom. I didn't sleep at all.

"The quality of travel depends not only on the carriages but also on the route," OBB Nightjet wrote in a statement to Business Insider. "We recommend the sleeper or couchette car for night travel. There is enough space to stretch out. Seated carriages are recommended for shorter journeys."

A few days later, I slept in a bunk inside a shared sleeping cabin for up to six people when traveling from Vienna to Venice for $84.

I still felt cramped in the 74-square-foot space, but having a lie-flat bed made sleeping a bit easier. I thought it was worth the higher price tag.

A year later, I traveled back to Europe to try out Nightjet's new overnight fleet with private cabins. I booked a room for myself from Venice to Vienna for $200. The added price for space and privacy made it worth the price tag.

My first two overnight Amtrak rides between NYC and Miami had WiFi on board. So when I got to my Amtrak train in Denver for my ride to Salt Lake City, I was surprised to find this route didn't include WiFi.

In hindsight, I should have checked if I'd have an internet connection before boarding. Had I known I wouldn't, I'd have downloaded some TV shows and movies for the journey.

While overnight train rides can feel exhausting, I think avoiding these mistakes in the future will make me feel cozier on my next sleeper train adventure.