Focused Cardiac Ultrasound
The LV should be 7cm in length and look like a football, a nicely shaped oval. If it appears global or looks like a softball, then you are foreshortening the apex of the LV.
To assist you in finding the Apical 4 Chamber apex have your fingers overhang your phased array transducer so that you can also use physical exam and find the PMI (Point of maximal impulse) with your fingertips.
Have the patient lie in the left lateral decubitus position for all views except the subcostal view.
If the patient has emphysema or COPD then asking the patient to exhale and hold the breath for 10-15 seconds may be helpful to obtain a clear view.