Depending on who you are dealing with, there are numerous ways to say goodnight. Obviously, how you say goodnight to your spouse will be different than how you do so with your best friend (at least it should be!). Here are some ways you can say goodnight to someone.
Use an informal form of goodbye when saying “goodnight” to friends or other acquaintances. You can use this either in person or on the phone. If you wish, you can simply say the word “goodnight” to end the conversation. “See you tomorrow” works well if you will spend time with that person the next day. Some people abbreviate goodnight when speaking. They'll say “g'night” instead of the actual word. This is especially popular when using instant messaging or text messaging (“gnite” or “nite” will be used). If you are saying goodnight in person, a hand shake or hug would be appropriate.
Tuck a child into bed when saying goodnight to her. This makes the child feel secure before drifting off to sleep. You can tell the child a bedtime story or say a prayer with her. Give the child a kiss on the head or cheek (or lips if you normally do so with the child) and say “I love you” before saying goodnight.
Let your spouse or significant other know that you miss him or her if saying goodnight over the phone. Being away from the person you love can be very difficult, especially during the evening. Make sure you let your loved one know how much you wish the two of you could be together. You could simply say “I miss you” or send a picture message over a cell phone of you with a sad face if you wanted to be cute about the situation.
Curl up with your significant other, hold him and say “I love you” as you both prepare to go to sleep. Lean over and kiss the person either on the cheek or lips as you say goodnight. If you want to mix things up and have a laugh, you could even kiss the person on the nose. The best part about saying goodnight this way is that you're not really leaving the person.
Be intimate with your spouse or significant other as a way to say goodnight. This is the most romantic way to end your day. It's also a good way to ensure that the two of you will a good night's sleep (wink wink).