Edit in JSFiddle

$("#myform").dform({
    "action" : "index.html",
    "method" : "get",
    "html" :
    [
        {
            "type" : "p",
            "html" : "You must login"
        },
        {
            "name" : "username",
            "id" : "txt-username",
            "caption" : "Username",
            "type" : "text",
            "placeholder" : "E.g. user@example.com"
        },
        {
            "name" : "password",
            "caption" : "Password",
            "type" : "password"
        },
        {
            "type" : "submit",
            "value" : "Login"
        }
    ]
});

<form id="myform"></form>

body {
    font-family: sans-serif;
    padding: 10px;
}

label, input {
    display: block;
    margin-top: 10px;
}