Figures of sound

Many figures rely for their effect through some emphasis upon the aural qualities of expression. These include:

Alliteration-repetition of the same sound at the beginning of two or more stressed syllables.
Paroemion - Alliteration taken to an extreme—every word in a sentence begins with the same consonant.(don't do this as it gets irritating very quickly) 
Assonance- Repetition of similar vowel sounds, preceded and followed by different consonants, in the stressed syllables of adjacent words.
Paromoiosis - Parallelism of sound between the words of adjacent clauses whose lengths are equal or approximate to one another.
Consonance -The repetition of consonants in words stressed in the same place (but whose vowels differ). Also, a kind of inverted alliteration, in which final consonants, rather than initial or medial ones, repeat in nearby words.
Onomatopoeia  - Using language whose sound imitates that which it names.

Figures of sound can be used anywhere you are looking to please or find favour with a judge or jury, as they please the ear. In moderation, they can be usefully used when opening, and also in a closing speech. They can be used at any point, but opening and closing is where they are most commonly found.