In Mandarin, how do you command someone to "wake up," "get out of bed," "hurry up and get dressed"
While I am on the subject, how do you call someone a "slacker," in Mandarin?

Question

Answer

wake up = qi chuang le (TC/SC起床了)
As to the phrase"get out of bed" in Chinese, we seldom use this kind of expression in Chiese. We just simply say " wake up" which means get out of the bed.
Hurry up and dressed up= kuai dian chuan qi fu (TC快點穿衣服) or (SC快点穿衣服) 
OR you also can say "kuai ba yi fu chuan shang" (TC/SC快把衣服穿上)

slacker = lan duo chong (TC懶惰蟲) (SC懒惰虫) means lazy bug for direct translation.
OR you can also say "lan duo gui " (TC 懶惰鬼)  (SC懒惰鬼) means lazy ghost for direct translation.
NOTE: TC= Traditional Chinese 
            SC= Simplified Chinese

Answer

日常生活中，只要简单的说，“快起来”或者说“快起来穿衣服”就行了。"slacker," 用汉语说就是“懒虫，懒鬼”之意。“懒虫“是可以说是一种昵称。

Answer

“起床啦”
“快点起来穿衣服”
“懒虫”
“懒家伙”

Answer

起來！  
起床了！ 
起來打扮穿衣呀。

懶蟲。（睡懶蟲）

Answer

赶快起床，大懒虫！