How does one legalise a civil marriage that was solemnised here in philippines so that my estate in the UK can be jointly owned by my spouse to be.
That is not necessary. If you are correctly and legally married in the Philippines then your marriage will be recognised in the UK. No mechanism exists for registration of foreign marriage. Your marriage certificate is sufficient to confer upon your spouse her marital rights.
However to add to that, if by the term estate you are referring to your belongings and property after you die, it would still be wise to draft a will. If you however intend your house for example to become jointly owned whilst you are still alive, then being married will not necessarily accomplish that. This last point only becomes important in a short duration marriage but in such cases there would not be a presumption of joint ownership where the house for example was titled in your name alone.