Please choose the correct ending to complete the given sentence: Health: [header] How to make yourself sleepy [title] Make sure your bedroom is sleep-friendly. [step] If you're having trouble falling asleep at night, make sure your bedroom is suitable for sleeping. Difficulty sleeping may be resolved by making a few simple alterations to your bedroom.

Ending1: [substeps] Change your sheets so they don't attract too much light and to keep the temperature level between 65 and 75 degrees fahrenheit (18 and 24 degrees celsius) in your bedroom. Turn off the lights if you're actually sleeping. Ending2: [substeps] Change your bedding, curtains, and/or blinds. Blinds are good options since they can cover up light and let in plenty of natural light. Ending3: [substeps] Keep your sleep life and wake life separate. Do not keep electronic devices like laptops and televisions in your bedroom. Ending4: [substeps] Shut all the curtains and remove your blinds from the windows. Provide a comfortable seat or chair for your bed and leave the doors shut.

Answer format: ending1/ending2/ending3/ending4