Quote from: Belish on November 01, 2017, 08:41:02 AM

1) Working offline generate address and private key at bitaddress.org - basicaly a paper wallet but I do not want to print it.

I don't recommend using this website. If you really insist, then you need to save it as a .html and use offline.

Quote from: Belish on November 01, 2017, 08:41:02 AM

2) Back up my private key in note files on 3 different USB flash drives. I know the machine and the drives have to be uncompromised.

Encrypt your USB drives.

Quote from: Belish on November 01, 2017, 08:41:02 AM

3) Send a small amount of my coins from Kraken to the address I created; check the blockchain if it is received; send the full amount to the same address if everything is OK.

Sure.

Quote from: Belish on November 01, 2017, 08:41:02 AM

I need long term cold storage but I want to keep it simple. As I understand I have to inport the private key in a software later in order to send the money back to exchange again? But everything is OK as long as I have the private key?

Yes and yes.

Quote from: Belish on November 01, 2017, 08:41:02 AM

1: should I do it?

If you have a significant amount of money in Bitcoin, absolutely. There are alternatives though, e.g. a hardware wallet.

Quote from: Belish on November 01, 2017, 08:41:02 AM

2: can I do it for alt coins too?

Not all altcoins have something like bitaddress.org, but I take it that you should be able to do something like this for the major ones.