You must know in advance that for what job you are applying. You also need to send a resume as soon as you will get a response. The personal profile information is very necessary and it should definitely be submitted on the online application form.
You need to read complete available job specification before you are applying to a certain job. Online Application forms can save you a lot of time as you skip many part of an employment like medical tests, interviews and assessment tests.
There are some information that doesn't need to miss from any application like contact, gender, number, citizenship, birth date and name. You need to submit all schedule activity and make sure that don't forget about the references. Qualifications, Employment history and special skills are also very important.
After filling out the applications, you should also expect getting more questions. You will generally find many sections in any standard application form. You will also find several questions related to your past job and experiences that are really help you in evaluating your past careers. These types of questions are really good as you will be able to decide if you are ready to perform the job that you are applying for.