Do i have to leave my PC online and open wallet or how does it work
No, create your own wallet at
https://wallet.shiftnrg.org, save your passphrase, send your shift coins from bittrex or whatever to your wallet adress and vote for delegates. please add 2nd. passphase (2fa) to your wallet for best security measures. make sure you dont lose your phrases, otherwise you wont be able to login to your wallet and your coins are lost.
best regards