Does anybody have any good tips on writing a good treatment when pitching a screen play?

A pitch and a treatment are two different things.

A treatment is a present tense narrative of the story describing
the action with no dialogue. This can be anywhere from a five or
six pages to more then twenty and will include the full story,
all the main and secondary characters and how they change and
develop.

A pitch is a short summary of the story.

A boxer with a loser mentality is offered a chance by the world
champ to fight for the title but, with the help of his lover
must learn to see himself as a winner before he can step into the
ring.

A pitch can be a little longer and go into more detail, but should
be concise and informational - no more than six to eight sentences.

Try this template:

(Title) is a (genre) about a (description of hero) who, after
(inciting incident), wants to (outer goal) by (plan of action).
This becomes increasingly difficult because (obstacles and
complications).