Now, I don't want to start trading every other day and stuff.
so... you want easy money without effort, is that it? sorry dude... but that doesnt sound good.
you dont need to be trading every day, but you will need to be "following" your investment every day. otherwise you will be probably losing money. this market is pretty volatile, in one day you have 100% profit and next day you lost everything.
if all you want to do is hold, i would say to stick with bitcoin.
Can I use only something like Shapeshift or something better?
yes, you can use shapeshift and other services like that(and that's an exchange too), but, in most cases, you will be paying higher fee's.