Mediation is by far the best way to solve these issues as long as it is safe to do so. You need to be able to know what you want, be able to speak your mind and at the same time be respectful of the other persons views.
If you are unable to do this and or there has been any domestic abuse which has had an impact on you that makes you feel at risk or be unwilling to sit in the same room then this is not for you and you must seek legal advice from a Solicitor and the availability of Legal Aid.
If you are considering mediation and not intending to go to court then please visit rainbowmediation.org .
If you are contemplating going to court then please do not use these mediation services. You will need to find a mediator through https://www.familymediationcouncil.org.uk/find-local-mediator/