Sorry I have been really struggling with this. I have more codes, but can't get pass the username yet. It wouldn't even send an alert. Below is just a portion of what I have. Thanks in advance. I just need suggestion on how to get first field (username) to validate and I can go from there.

function validateForm() {

    var userId = document.myForm.userName.value;
    var password = document.myForm.passwordOne.value;
   var passwordVerify = document.myForm.passwordTwo.value;
    var fName = document.myForm.firstName.value;
    var lName = document.myForm.lastName.value;
    var emailAdd = document.myForm.email.value;
    var phone = document.myForm.phonenumber.value;

    if (uName(userId)) {
        if (validatePassword(password)) {
            if (passwordCheck(password, passwordVerify)) {
                if (onlyLetters(fName)) {
                    if (onlyLetters(lName)) {
                        if (validateEmail(emailAdd)) {
                            if (phonenumber(phone)) {
                            }
                        }
                    }
                }
            }
        }
    }
    return false;
}


function uName(userId){

    var userId_len = userId.value.length;
    var alphaNumber = /^[\w ]+$/;

    if (userId_len == 0)
    {
        alert("User Id should not be empty");
        userID.focus();
        return false;
    }
    else if (userId.value.match(alphaNumber)) {
        return true;
    }
    else {
        alert("User Id should be alphanumeric");
        userId.focus();
        return false;
    }
    }