"Designing things" is a little broad, is there something more specific you would like to design?
Designing in Civil Engineering is generally done by Architects doing space planning, etc. Structural Engineers do structural design, (and a PE puts his name and stamp on the thing guaranteeing it won't fall down and if it does he's the one to blame).
Architects generally do more of the "sexy" designing. Structural types do mainly the non-sexy. (CE). Here is a Design-Build firm that does "sexy" stuff near me
http://www.creativeconstructors.com/projects/flamingo.asp
In ME land, I've seen basically three schools so to speak (I'm sure there's more).
1. System design engineers, for example, a team that designs a component of an automobile, (brake system). I have a friend that is on a system team for GM. He loves the **** out of it, but the system isn't that sexy in my opinion, (I honestly forgot, when I asked he treated me to a 30 minute dissertation - but he was sure exited about it, I think he was awarded a patent or three).
2. Research and Development (R&D). Designing and building a new "thing" like a novel widget that does something cool and saves a lot of money, energy, etc.
3. Production Design. The manufacturer has a billion dollar contract to make X number of widgets (maybe from the firm from #2). Design a process that can meet or beat the production and profit goals.
Since you said "Design new things and make them work" let's pick #2.
So I'd recommend researching companies that design machines that improve energy efficiency, like solar panels, wind things, self-lubricating nano-metals etc. Google "green" jobs in your area and you can see what employers are looking for in a design engineer.
Now, I preface this with saying "I love you man" but I'm going to have to knock you down a peg or two. Here's why.
Lets say you really like rims. You want to design cool rims. Let's say not even automobile rims or ATV rims or rims that require SAE standards, or require any kind of standards at all. Let's say Golf Cart Rims.
So you decide to work for a Golf Cart Rim manufacturer company that has been in business for 30 years. They have an internal design and engineering dept. But, for some reason even though they are a successful business for 30 years, they have no one that has a clue how to design a good golf cart rim. The shareholders of the company who have invested thousands / millions of their money into this business think you are a good fit for the future of their company.
So you design some rims, show them to the marketing dept and the bosses etc and you get the green light for production.
So as a good engineer you spec it out and have the drafter make up drawings. Some prototypes are made and you put them on the wall by your desk. Then you start working on the next rim design.
So the company makes 100,000 rims and sells them all to golf cart manufacturers.
Then one day you get an email. Its the golf cart manufacturer. They are getting complaints from their customers. The rims keep cracking at the lugs, which then the paint peels off too. Hmm weird they shouldn't be cracking, the steel thickness is fine. You walk down to the line and see workers grinding down the inside hub because it doesn't fit on the assembly machine, (no one told me I needed to supervise and QA the production process!). Then you look at the paint that purchasing got. Its to spec but unfortunately the supplier dumped their inventory of chinese paint that has lead in it (was a great competitive price though!)- and your purchasing guys and inventory guys missed it, (no one told me I had to QA every material and component of my design!). Then you get calls from lawyers of individuals and companies, and golf courses (your lead paint is littered on every golf course in the world now), you google your name and you see news articles, etc etc etc.
The bottom line is, who the f--- is going to entrust you to design something right out of college? No one is. If you want to design something all by yourself start a company and design it. If no one wants to make it, the design sucks, and there is a reason why.
Until then, look for a company or group of folks that make or design something you like, then join them. Maybe you'll find a small company founded by a guy trying to make floating bombs but his company is making bullet casings to pay the bills. So, he puts you on the bullet casings so he can focus on the floating bombs. So you figure out bullet casings then he asks you to help out with floating bombs. You design floating shoes while trying to make a floating bomb and get an investor, then you hire a new grad to do the shell casings so you can focus on the floating shoes. The new grad you hire says I want to design floating shoes, then you say - dude you don't have a clue on floating shoes, first figure out bullet casings then you will have a clue, then we'll talk floating shoes and floating bombs.
You may be doing something you feel is mudane off the bat but later you will find it is important because its kinda a big and important thing designing something that other human beings use safely and profit from it.
After a while you'll see what to focus on, what matters / what doesn't and you will probably be in charge of designing something, maybe sooner, maybe later, by yourself or you might have a team.
