Text before quantity

Please post the url for your site.

.quantity:before {
  content:"Select your quantity:";
  margin-right:10px
}
.quantity input {
  display:inline;
  margin-right:30px
}
.woocommerce-variation-add-to-cart {
  margin-top:20px
}

If you have WP 4.7, custom css is entered at:
Dashboard > Appearance > Customise > Additional CSS