Take a look at these sites for advice on how to tackle each of the four components of the DELF exam
Take a look at the rubric that is used for the writing section of the B1 exam.
Take a look at the rubric that is used for the writing section of the B2 exam.
Here's what the examiners are looking for during the oral interview.
Here's what the examiners are looking for during the oral interview.