How do I protect my game without ruining myself!

First, your English is excellent considering it’s not your native language. However, I am not clear what you meant by “Pathentory”? What would this thing do for you (this would help us narrow down what you meant)?
TO properly protect your title.

Step A) STOP worrying! The chances that someone will swipe your product are very low!

Step B) In America when a book is written we apply for a “Copy Right”. This means that other cannot copy or “plagiarize” our work. I am certain you have something similar in Sweden. Go out and get one, this gives you a “proof of concept”. This will allow you to (in a limited manner) protect yourself.

Step C) GO OUT and get some play-tests done! Accept ANYONE that will play your game and stop being fearful of thieves!

Finally, when you are ready to send it to a company, just send it. Stop worrying about thieves and dishonest folks. I find that most designers waste more time worrying someone will steal their design then they do designing! Go get some testing done, relax, and when it’s ready just box it up and send it. The last person you should worry about stealing your game is a large game company. They won’t, they just won’t.

E

Go ahead and publish it in a public forum, such as this. That basically gives you a copyright by proving you had the design at this date.
If you want an official copyright from the U.S. Govt it only cost about $25 and lasts a lifetime and is easy to do.
Dont bother with a design patent. It is difficult to do, cost more than you will ever make off the game and only lasts a few years. But there are a million game ideas out there. Very few are valuable enough, (in money terms) for someone to steal it.
Enjoy your game.

Others already said all the standard advice about how to not be afraid.

Also living in Sweden I'd like to add the following about copyrights:

Like all countries that have signed the Bern Convention (Sweden since the early 20th century, US since 1987, most other countries in the world too) you get automatic copyright protection the second you create something. I know in the US they still have a system where you can register copyrighted works, but I never heard about any such thing here in Sweden. You simply create your cards, and your rulebook, and copyright is all yours. It is good of course to print "copyright 2013 by (insert name here)" on them just so people know who owns the copyright. As other said, making sure your work is public will ensure that everyone knows it was your artwork/text originally.

Also trademarks do not need to be registered. Just put TM next to your trademark and it is yours. However protection will be much better if you register it (Patent och Registreringsverket in Sweden, I would guess) and that is when you can put a little R in a circle after the trademark (at least that is how it works in the US; I never bothered to read up on how it works exactly here in Sweden).

Nothing will protect you from similar games anyway. Not likely to be your biggest problem though. You need to get the game out and playtested by people that do not know you or your friends. If this is your first game, I must tell you that odds are not that good that it actually will be as great as you think. Focus on it like a fun project and a learning experience and don't get upset if publishers will turn your first few games down no matter how great they seem to you. Don't waste money on artwork or rules layout, that the publisher is likely to redo anyway before the game is ready.

And if you are going to Lincon this spring to demo your game, let me know. :)

While lewpuls' point about L'Attaque being the predecessor of Stratego is a bit misleading (since L'Attaque DID have a patent, and the patent ran out literally over a century ago, and Stratego wasn't made until 35 years or so after that), the point is good that the only real protection is in the social constructs around the hobby.

Don't waste money on a patent, even if you're awarded a patent, most get thrown out in court based on prior use anyway. The understanding of game design by the layman is not high enough for any normal court to grasp what is and is not an original characteristic. Even the average non-layman doesn't have a solid enough grounding in it, to be honest.

Someone like Hasbro will not publish games by independent designers, and will usually only buy the rights to games that have already been published and proven in the marketplace.

30 people isn't enough to know if your game will be a hit. Contact publishers yourself, pitch your game to them in person at conventions such as Essen in Germany, or self-publish and sell your game at a booth in Essen. If it's a hit at the fair, other publishers will be interested in reprinting and/or distributing your game.

Essen is the best barometer, as its the largest boardgame convention in the world and hundreds of new games are released there every year. If your game is a hit there, then you've got a good start.

In what country to you live?

Here’s a practical step designers could take to protect their work.

Start a daily log of ideas, work done and influences. Influences include names of play testers and people you discuss design with. Find the least expensive bound journal type book which is cheep and available enough that you can buy a 5 to 10 year supply before the manufacturers change them. They need to be bound so that missing pages are easily identified – and then NEVER take a page out. Write in it every single day.

I use standard composition books widely available in the USA. They typically cost one US dollar for a 100 page book. If I write on both sides of each page then a comp book lasts about 2 months, so a 10 year supply is 60 US dollars for 60 books, You might want to look around and see what is commonly available where you are.

On each page write the date, time, page number and topic title. For me the topic will be the word ‘Idea’, ‘Work’ or ‘Influence’ followed by a 1 to 4 word synopsis of what I’m writing about. When you switch from one topic to another draw a line between topics and put in the date, new time, and new topic title.

Leave a consistent margins and space between topics. If you start new pages for new days or topics then ‘X’ out the empty space at the end of the previous page. Use pen, not pencil, and the same pen for the entire topic The whole idea is to make it obvious to anyone looking through these that there isn’t any way to easily edit stuff later.

Store the filled-up journals off site, and if possible photocopy or scan them so you can store the copies elsewhere.

Best of luck,
- KrisW

If you Google "mailing things to yourself" you can find several articles that cover this in depth.

Or click one of these -

http://www.plagiarismtoday.com/stopping-internet-plagiarism/your-copyrig...

http://www.plagiarismtoday.com/2006/08/25/the-myth-of-poor-mans-copyright/

- KrisW