Shooting my first wedding I quickly learned that I have to have a plan, a map when shooting on a wedding day.
Ireland is an island full of surprises. You cannot rely on the weather forecast because the wind can decide that it is suddenly the right time to rain.
The factors you should consider on a wedding day is rain, sun and a map of the route.
Once you know the name of the venue, a week before the wedding go down to the venue, and check it out.
Make sure that Indoor Premises have accommodation for photographs in case it rains. Rooms with white ceilings is your best bet. This is because you will bounce your flash off them without creating any sort of coloured casts. If you bounce your flash off a wooden ceiling, for example, you will create orange casts on people's faces.
Rooms with large windows placing people opposite them, hence facing the window instead of placing them with their backs towards them resulting in fogginess in your pictures.
Sun can be as bad as rain. When you are on the property, calculate the approximate time of the day you will be taking photos outside and make sure you know the position of the sun on that day. Mind that sun changes it's positions noticeably every two weeks. So coming over a week before the wedding should suffice.
Make sure that the sun isn't shining right into the couple's faces, that it's behind them. It will create a shadow on their faces avoiding those annoying eyes, nose and chin shadows as well as squinting!
Going around the property of the venue on a dry day create a short route that ends up in a loop. No matter how easy the wedding dress will be to walk in, it will always be tiresome for the bride to walk long distances. Mind that she was up since early morning and up on her feet ever since.
If it's a cloudy day... You are in luck!