If you believe that your child is being cyber bullied, the first step you need to take is to contact the school or youth organisation if the bullying involves another pupil from that school or youth group.
Once this is done, you should also contact the service provider through its customer care or report abuse facility. If the cyberbullying is of a serious nature and potentially criminal you should also contact your local Gardaí.
How to contact service providers:
Video and Photo Sharing sites (e.g. YouTube, Instagram)
If someone posts a photo or a video that violates your child’s right to privacy on a website, you should fist get in touch with the uploader via the messaging function and ask them to remove it. They may not realise that your child is uncomfortable with the posted material. If they refuse to remove it then you should contact the website operators regarding your concern. If the content is inapproriate or in breach of their terms and conditions they should remove it from the site within a specified amount of time.
How to report content on YouTube:
How to content on Flickr:
Social Networking sites 
If you have an issue with your child being bullied on a social media site then you should report it to the operators of the website. This can be done by using the reporting tools on each website,  for instance on Facebook click on the ‘Report Abuse’ link.
You can report abuse on the Bebo site by using the Contact Us link:
There are similar services available for other Social Networking sites such as:
If you are experiencing difficulties with other Social Networking Sites
not listed above, you should contact the site administrators directly
for advice and assistance.
Ask.fm does not seem to have any process in place to report abuse.If your child is using the app through Facebook, you will be given an option to report the application by clicking on “report/contact this app” which is displayed in the final tab in the right-hand column.Besides this, the block function seems to act as a form of reporting abuse however there is no evidence to suggest that moderators of the site are alerted to inappropriate content through the blocking process.
Internet Chat
Windows messenger Live
Report inappropriate behaviour on MSN Messenger by notifying Microsoft using the form on this webpage:
Yahoo Messenger
Mobile Phones
O2 Customer Care:
1909 (Bill paying customers)
1747 (Speak easy prepay)
1850 601 747 (from a landline)
Vodafone Customer Care:
1907 (Bill paying customers),
1850 20 87 87 (Ready to Go)
3 Customer Service:
From your 3 mobile 333,
From other phones 083 333 3333
Meteor Customer Care:
1905 (Pay Later and Pay As You Go
Read more about cyberbullying here