It depends on what type of player you are. Do you prefer open or closed positions? Symmetrical or inbalanced? Aggressive or defensive?
There are too many openings and you need to find what types of situations you prefer. I can help you, but I don't really know where to begin helping you.
what openings do you play?
mostly I open with e2-e4, bishop and knight
I Like to play offensive
I don't think there is a player that prefers to defend rather than to attack. The first opening I learned was the Kings Gambit, it gives good open lines and is sure to be a sharp tactical battle. I also like the Italian game and the Ruy Lopez is good too. Those are good openings for white, for black, against e4 the sicilian is king and it's good to start there. Against d4 I like to play the Kings Indian and QGD, depending on the time limits, shorter time limits I'll play more QGD, longer time limits I play KID.
Absolute best advice, that I wish someone would have given me a year ago: join a group that plays a lot of vote Chess, and pay attention to what they say in the discussions and how they play the opening. You will learn the most useful information, in the shortest time.
Hope this helps - good luck!
Get "Fundamental Chess Openings" by Paul van der Sterren. It explains the ideas behind all chess openings, with lots of words, especially written for low rated players. It's perfectly suited to be a first opening book.
(edit: the page http://www.gambitbooks.com/books/fco.html has a PDF with some example pages, on the Slav)
who can help me improving my openings
read chess openings
i just saw through 10 of your last losses and it seemed you lost them all because of tactics and not because of opening:) yes you should study a little opening but not much. just a little of ideas and themes but not trying to memorize every single possible moves. learning your openings better than your opponent will increase your rating maybe 20 points. studying tactics and endgames and looking through some middlegamebooks like jeremy silmans reassess your chess will take you to at least 2000 in rating by knowing almost nothing about openings. when you get there memorizing openings start to matter
who can help me improving my openings