As a PhD student, my food budget is low enough that I frequently eat ramen for lunch or dinner. This is actually not completely out of necessity, but also partly by choice: a properly made ramen is delicious, comforting, and filling.
Choosing the Right Base
Just like a good steak can't be made using poor quality meat, you need to start with a more up-scale ramen brand in order to produce great-tasting ramen. The 10-cent Maruchan ramen at your local supermarket is the wrong choice! Instead, set your budget a bit higher. A good ramen would have noticeably higher quality noodles and soup mix. You may need to visit an Asian market in order to pick up some of the more premium brands.
A popular choice is Nongshim Black, which contains oxtail and beef bone extract for a rich flavor. Unfortunately, Nongshim Black is the most "expensive" ramen, costing around $1.50 a packet.
Choosing the Right Toppings
I eat ramen because I'm lazy and it's cheap, so it wouldn't make sense to add expensive toppings or toppings that take a long time to prepare. As I do not cook during the weekdays, fresh vegetables are out of the question as they easily spoil. Instead, I prefer adding frozen vegetables, such as frozen peas, corn, and spinach. Also, adding some dried shiitake mushrooms goes a long way for adding flavor and make the dish more visually pleasing. They're also incredibly cheap: you can buy a bulk pack for around $7 that will last you quite a few months. Since they are dried, they last for years without going bad.
Adding egg also vastly improves the look of the dish as well as the richness of the broth. I like to beat up an egg and slowly pour the mixture into the boiling water while slowly stirring, resulting in wispy eggs similar to those in egg drop soup. In addition, if I'm extra hungry, I'll add in a whole egg to the pot and poach it.
I like to have some meat in my meals, but fresh meat is expensive and doesn't last very long. In addition, you would probably need to pan fry the meat to make it taste good, and I don't have the time for that if I've decided to make ramen. Instead, I usually add frozen meatballs (bought from the frozen food section for ~$3 for 1lb) or sausage (not hot dogs!). A benefit of living in Texas is that there are literally hundreds of different brands and types/flavors of sausage. It's fun trying the different types and seeing which ones taste the best. Sausage generally comes pre-cooked: you can prepare it by thinly slicing and putting it in the water near the end. Frozen meatballs take more time to cook (as they are frozen and not refrigerated) so put it in near the beginning.
Sometimes, people have "secret ingredients" that supposedly improve the taste of ramen. I recently learned of adding in American Cheese or peanut butter to the broth. Supposedly this will improve the richness of the broth. I have yet to try either one, but I will report back after I do so. Both these ingredients meet my requirements (cheap, easy to prepare, lasts a long time) so if I discover that it tastes good, I will continue to do so for a long time.
As for my own secret ingredient, I will share this to the world for the first time ever: "Lao Gan Ma" brand hot sauce! This is a "fried chili" type of hot sauce, which adds spiciness and savoriness to your broth.
The Final Result
Udon/ramen packet: $0.75
Sausage: $2.50/4 = $0.63
Eggs: $1.50/6 = $0.25
Meatballs: $2.50/12 = $0.21
Shiitake Mushrooms: $2/10 = $0.20
Frozen peas and corn: $1/20 = $0.05
Hot sauce: negligible
Total cost: $2.09 for a delicious, hearty, and fairly well-balanced (except for sodium) meal!
Disclaimer: this photo was taken using instant udon rather than instant ramen, but the execution is identical.