You can buy bitcoin, and then wait for it to rise, you can also see the signature campaign, so that it can get bitcoin.
Buying and holding bitcoins is not an steady way of earning bitcoins because you don't know what will happen in coming time, sometimes it grows and sometimes it drops so that cannot make you steady earnings, signature campaigns can do that though as their rates are fixed.
Yeah holding will never give you steady income in fact holding can bring loss if price drops in future and now the days are gone when price used to fluctuate in quick session, price is getting stable now.