In my personal experience, it's hard to manage your greed when it's a bull market. Because in a bear , you won't get influenced by greed because you don't get money a lot and greed is where you want to have more after you get something which is not possible in a market that does not do good. The best thing to do to deal with it is better to experience your mistakes to not do it again or the other one which is sell 70% - 80% as always like it's your trading rule.