Select {% include 'elements/forms/select' %}
#
HTML 
<div class="field-set">
    <div class="field-set__content">
        <div class="field-set__items">
            <div class="field-set__item field-set__item--select">
                <!-- Multi field so this is a label - it will be visibly hidden though -->
                <label class="field-set__label field-set__label--select">Title</label>
                <div class="field-set__input field-set__input--select">
                    <div class="custom-select">
                        <span class="custom-select__selected-value"></span>
                        <select class="custom-select__input" id="your-role" name="selecta2">
                            <option value="mr">Mr</option>
                            <option value="miss">Miss</option>
                            <option value="mrs">Mrs</option>
                        </select>
                    </div>
                </div>
            </div>
        </div>
    </div>
</div>
Twig 
<div class="field-set">
    <div class="field-set__content">
        <div class="field-set__items">
            <div class="field-set__item field-set__item--select">
                <!-- Multi field so this is a label - it will be visibly hidden though -->
                <label class="field-set__label field-set__label--select">{{label}}</label>
                <div class="field-set__input field-set__input--select">
                    <div class="custom-select">
                        <span class="custom-select__selected-value"></span>
                        <select class="custom-select__input" id="your-role" name="selecta2">
                            <option value="mr">{{values.1}}</option>
                            <option value="miss">{{values.2}}</option>
                            <option value="mrs">{{values.3}}</option>
                        </select>
                    </div>
                </div>
            </div>
        </div>
    </div>
</div>
{
    "label": "Title",
    "values": {
        "1": "Mr",
        "2": "Miss",
        "3": "Mrs"
    }
}