After you have found a service provider for your project you need to send him an invitation to work on it. If you want first to discuss your project or his/her proposal details, you can send him/her a Personal Message.
To send a personal invitation, choose the provider's bid from the list of bids on your project and click "Invite Provider". Choose a project you would like this provider to work on and click "Invite Provider".
Service Providers can either accept or reject your invitation.
If a provider rejects your invitation, bidding continues.
If a provider accepts your invitation, bidding is over, the project passes into the stage of negotiation, where you can discuss all the details, upload additional files, confirm your project budget and project implementation terms.
You can invite another provider if your currently selected provider has not accepted your invitation. In this case the first invitation is canceled.