Enter the radices: For example, consider كتب, it has the radices kaf-ta-ba. Simply select the radices in a right-to-left order in the radix selector. You should enter the verb in it's perfect form!
Select the forms: ACON conjugates into the first ten forms (marked by the Roman numerals I to X). For example, if you want to conjugate انفتح you enter the radices فتح and select form VII.
Form I vowels: When conjugating in Form I, do select the vowels corresponding to the verb. This is not mandatory in the case of sound verbs but weak verbs can be drastically changed by the vowels one supplies.
Click the "conjugate" button