First, you want to make sure the panel can screen for respondents based on your experiment design. Sticky experiments support computers (laptops or desktops) and mobile devices (smartphones and tablets). But devices cannot be interchanged, i.e. if an experiment is designed for computers, participants can only run it on desktops and laptops, not mobile devices. Similarly if an experiment is designed for mobile devices, participants cannot run it on computers.
Secondly, you want to add in a survey question to make sure they have a webcam on their device. It can be an external or internal webcam. Here is an example of a question you can use:
Do you have a working webcam on this device?
Third, you want to make sure the respondents are comfortable with taking an eye tracking experiment and are willing to allow us to turn on their webcam. Here is an example a question you can use:
This study includes an eye tracking portion. Would you be willing to participate? All data is reported anonymously. You must select yes to proceed with this study.
Not right now
If your experiment uses the web element, the participant will need to share their screen, so the same thing applies; although Sticky automatically asks for the user's consent, it is good practice to have an explicit question asking the user.