On most of the online forms, not all of the information is "mandatory". In many cases, however, it is not easy to quickly identify which of the fields are mandatory.
It is important to clearly differentiate between mandatory input fields/optional input fields (or vice versa).I
The solutions used in order to differentiate between these input fields may vary. In most cases an asterisk symbol used in front of some fields tells the user, whether the latter is mandatory or optional. In all cases, clear instructions should be presented early in form and not the end.
How information should be entered?
In this part, we should discuss about the different formats for data entry. For example, the inclusion of a date of birth can take several forms, depending on the country (or culture) in which there is: For example, in France: DD/MM/YY, DD/MM/YYYY, DDMMYY.
This type of information is quite useful for expert users, but it is sometimes necessary to provide a concrete, example: 15/01/2001. Knowing that people of diverse backgrounds may have to complete the form, the appropriate instructions about the format used must be given,
The organization of input fields
The fields must be organized, in an order that is relevant to the tasks users. For example, fields related to the postal address will be presented in an order the user expects. In this case, however, not only special attention should be paid to the organization of fields but also their relevance (compatible to the peculiarities of various countries).
In other words, the input fields should be organized:
according to the source of information to be entered
according to semantic information (address, zip code, city, etc..)
the logical sequence to fill a form (if a predefined order can be established),
focusinG on important fields (fields required/optional) or
by the frequency for filling the fields.
Separating entry fields
To enhance the readability of visual forms, input fields must be grouped and the groups must be separated from each other by spaces, frames, colors or other visual cue.
The organization of fields and titles
When must we align the field titles to the left and when should they be aligned to the right?
The positioning of the field titles depends on simple rules. When titles do not differ in length (by more than 6 characters), they can be aligned to the left, otherwise set them to the right (if they can't be shorten).
Field length (number of characters) should be adapted to the expected length of the data to be entered.