Lets start from the very beginning.
Invitation link
Have you been invited to conduct a check? Have you received a link that looks like vl.ink...... via text message directly to your mobile number from your Solicitor or Agent? That is the first thing you would need.
If not please contact your solicitor and request that they send you invite/link via SMS/text message.
Mobile Device
Identity document: i.e. passport, drivers permit or ID
Proof of address documents
If you are buying, gifting, renting or a guarantor, proof of funds will be required.
Refer to specific articles for more info.