Hi there, I'm new to altcoins. Anyone has some usefull tips? Or a strategy that worked for you? 
When i was new to the cryptoworld i also have the same queation. How do i start? Well, what i did was buy bitcoin and trade the with the altcoins. If you want to know which altcoin would guarantee growth in your investment, the answer would be none. Growth depends on how you hndle your coins. Some people mine, some people gamble, some people do day trade, some people ghold their coins. If you wnt to be safe, just stay with the coins that has already built their names: bitcoin, ethereum, litecoin, etc. Good luck!!
If you are a newbie, you need to consider some important things to do before to get involved to any kind of business. Don't make a rush to give your money immediately even you are not satisfied the information. Don't give your trust to someone you didn't know. Make sure that you know the official website before to join in an online business. Just refer from person who really got further experienced on it. And also do your own research so that you will know if the business is really good for investment or not.