Translation:Don't bring too much luggage.
This should also accept "Don't take too much luggage". 带 means both "bring" and "take" and this sentence could be told to someone you'll travel with, someone who will be travelling from elsewhere to come visit you, or to somebody who will be leaving you to travel without you. In the last case it would be "take". In the second case some people might say "take". Otherwise it would be "bring".
That is also acceptable; both of the following sentences are fine then:
- 不要帶太多行李 (casual)
- 別帶太多行李 (with 別)
It is the opposite. 别 is rather colloquial. You can see signs that say “不要/不准/不许/禁止 随地吐痰” (no spitting), not 别随地吐痰.