Garden lumpy, bumpy & prone to flooding

Naf

My new garden is just full of lumps and bumps, and to make matters worse, every time it rains, it just becomes a pond.
What can I do
a) to improve drainage so it doesn't flood to begin with, and doesn't just stay muddy
b) to level it out a bit so it's flatter?

Thanks for any advice.

Farway

Is this a new build house? Are you at, or near, the bottom of a hill?

I ask because if it is new build then it may be likely your garden is just builders old broken bricks, cement mixer droppings etc

Check here [Environment Agency] , put in your post code to see if you are on a flood plain for instance, builders often build on them

Naf

1950's council house. The area's pretty flat really.
And not even within the area of "extent of extreme flood" - that's quite a distance away.