Make sure you have a good reason for the check. It will only be accepted to counter vandalism or disruption to Wikimedia wikis. Valid reasons include needing a block of the underlying IP or IP range, disruptive sockpuppetry, vote-stacking, and similar disruption where the technical evidence from running a check would prevent or reduce further disruption.
Be specific in your reasons. Ambiguous or insufficient reasons will cause delays. Explain the disruption and why you believe the accounts are related, ideally using diff links or other evidence.
Make sure there are no local checkusers or policies.
Reason(s): All three accounts contribute in the same field (Greek TV, especially NERIT and Eurovision) and in this case Jeanis12345 and his IPs has already voted twice against merger one as IP (220.127.116.11) and one as Jeanis12345. If i'm not mistaken, 18.104.22.168 has signed in a conversation as Jeanis12345. C messier (talk) 12:41, 28 July 2014 (UTC)
@C messier: I am not sure of the reason for the checkuser, stewards would not normally publicly align a user account with an IP address. This looks to be a case of It looks like a duck to me, and I am not sure of any advantage of running the checkuser. — billinghurstsDrewth 13:56, 28 July 2014 (UTC)
Reason(s): Similar editions and comments in articles. It seems they are same persons using various usernames. Very similar editions and comments in articles. Please check this 2 users, thank you. David1010 (talk) 18:53, 29 July 2014 (UTC)
@David1010: What is the purpose of the checkuser? Why does it need a checkuser? Are they in breach of a policy? If so which? That people make similar edits or comments is not a sufficient reason to undertake a checkuser. If the editors are problematic, they don't need a checkuser, they can be managed by blocks, conversation, etc. — billinghurstsDrewth 23:39, 29 July 2014 (UTC)