Try to get some verticality in your dish. Everything just laid on a plate is boring. Instead stack your meat on top of your potatoes, stand a large asparagus spear upright, put some onion straws on top of your dish. Anything that gets some differing heights to your dish will make it more visually appealing.
Use your colors. Avoid dishes that come out with nasty colors, or do something to correct them. My wife likes to select vegetables that have complimentary colors. It makes the dish look more interesting than if it is mono-tone. You can sprinkle fresh herbs over the top to add some more color and flavor.
Add some flair. You see this all the time with desserts in restaurants but can do it with thick sauces on a main dish too. Put sauce on your dish in a nice pattern and then run a tine of a fork through it at a perpendicular angle to make sharp streaks through it. Dollop a sauce in a spiral pattern in ever smaller amounts so that you get smaller circles around the edge.
Watch Grant Achatz at Alinea preparing a dessert straight on the table. If this won't inspire you, nothing will. He uses all three things I mentioned to make this interesting. Not to mention that he's doing it straight on to a silpat table cloth. And one of America's greatest chefs makes dessert for you table side, there's more than a little "presentation" in that alone. We ate there for our anniversary, and he signed a copy of his book for us, even his signature uses the circles and lines so common in dessert prep.
The two tools I have used to make my own pasta are rollers and extruders.
The extruder sounds similar to the pressurized tool you described above. It uses an auger like a meat grinder and produces round pasta like spaghetti. Shells and macaroni are also made by extruding. The material that the die is made from with affect the texture of the pasta surface. The one that I used was an attachment to a stand mixer and costs ~$100.
Pasta rollers have a couple precision rollers with variable spacing for forming the pasta and a set of cutters for slicing the pasta into linguine. There are various sized cutters- my cutters are just one size. The rollers are also a fairly simple machine and can be powered, a stand mixer attachment, or rolled by hand which I have. My hand cranked rollers cost ~$50 new.
Rollers are easy to get used because they are the kind of thing that people get for wedding gifts and never use- like yogurt makers. I got mine unused at a garage sale for $5. This bit of information may not be applicable to you in Germany. :)
Best Answer
The answer is in your third picture -- chopsticks.
Grab the bunch with the chopsticks, twirl it around, then slide the chopsticks out.