It's a lot easier to reverse out of a space than it is to reverse into one, especially when you feel like you are being watched.
This is crazy advice. To start with it's much easier to reverse when the car engine is warm - it's one of the many reasons why if you are parking you should reverse in to a space when you park and not drive nose in.
As @LadyPoison says more importantly, reversing out of a space is far more dangerous as you haver restricted visibility.
@Ozanj
Reverse parking is mostly practice and knowing the car and getting a feel for it's width, size and 'turning circle'. So a new car will always take time to get the hang of. My own car I've had for years so can reverse park it really well and easily but my DH's car is new and I find that really tricky.
My tips would be
go to quiet road and find a single car parked by the car with nothing round it.
Pull up directly behind it (as in the position you would be in if you had reversed parked there) then drive forward very slowly so as to position your car parallel to that car (as in the position you would be in if you were starting a reverse park maneouver).
As you move through that path very slowly, keep stopping and check the rear view mirror/back of your car and pay particular attention to the ANGLE of that back of your car to the kerb as it moves through that arc.
Do this a few times (forward) so you get a hang of what the positioning should look like. and how far you should be turning the wheel.
Then try it backwards and practice a few times.
I never really got on with the whole start half a car length along advice as it never worked for me. For me I found it easiest when I focussed on the back of my car and the angle to the kerb so then I got a sense of when I was on the right line or not.
Or as others have said, book a driving instructor for a lesson purely on reverse parking and ideally to teach you in your own car.