How to pre-fill Contact form 7 select fields

We want to prefill customer’s order based on what he clicks.

For example on click “Objenat”

the customer is not only redirected to the page with the ordering form, but the form is prefilled with “Novorodenecke fotenie” like so:

And, more advanced. On a click from the price list, e.g. from “Cennik rodinne fotenie a fotenie deti” click on “Narodeniny”:

two fields in the order-form are pre-filled:

I have found instructions on how to pre-fill these fields on on We add default:get to he definition of the field:

<label> Objednávam si:
[select moznosti default:get "" "Novorodenecké fotenie" "Tehotenské fotenie" "Rodinné fotenie"   "Iné fotenie"] </label>

And the URL with paramaters has to contain parameter in the form moznosti=Novorodenecké%20fotenie where the space is replaced with the URL code for a space, “%20”.

So now, we have to replace the hyperlinks on buttons like so:é%20fotenie