A few suggestions for your unit to run more efficiently

1) Keep the exhaust hose as short and straight as possible.
2) Heat is emitted back into the room as hot air travels throught the hose, try insulating the hose.
3) If unit is to be operated thoughout the day, turn on the unit early, before the noon heat hits.
3) If unit is to be operated at night and outdoor temperature is lower than room temperature, first open windows to allow air exchange. After 15/20 minutes, close windows.
4) When unit is turned on, set fan on High to allow air circulation. After 30 minutes, set fan to Low. In low fan, air is allowed to pass through the cooling coils over a longer period of time, thus the air output will be colder than High fan.
5) For units with Self-Evaporating Technology, it is always suggested to not use continuous drainage in cooling mode. Allowing the water to collect and recycle helps cool down the cooling coils, which in turn produce colder air output.