Don't Neglect Back Work
The vast majority of people dedicate far too much time to chest work than they do to back work.
As a result they often develop rounded shoulders as the internal rotators get over worked and the external rotators become lengthened and weak.
This can lead to bad posture can often lead to people slouching and sometimes looking more 'out of shape' than if they had great posture.
Rowing movements are fantastic to develop mid back strength and enhance posture.
To perform a row correctly begin by retracting your shoulder blades and then immediately bend the elbows to continue the rowing motion until your forearms make contact with the upper arms.
Make sure you do not use the lower back to assist the lift.
Check out Lisa McDougall performing chest supported rows in her 1:1 session in preparation for her wedding in a few weeks with SOS director Sam O'Sullivan.