Simple:
* Daring dog
* Dreamy day
* Delicious dessert
* Dangerous drop
* Deep dive
More Complex:
* Dazzling diamonds dancing daintyly
* Daring deeds done during dawn
* Deeply disappointed during dinner
* Dangerous darkness deep down
Humorous:
* Dumb dinos dancing disgracefully
* Dizzying disaster during dog show
Remember: An alliteration is the repetition of the same consonant sound at the beginning of words. You can use your creativity to come up with even more alliterations starting with "D"!