New Cast iron griddle pan

Anyone have a good idea of how to season it nicely?

what brand is it? If it is a "Lodge", they come pre-seasoned.

Here are my instructions copy and pasted from a previous thread
After cooking, clean with hot water and a stiff brush. Never use harsh detergents to clean iron as it will remove the seasoning. Avoid putting very hot cast iron into cold water as the thermal shock can cause it to warp and crack. Dry the cast iron pan thoroughly.
Store your cast iron in a cool, dark place. if it has a lid, place a paper towel between the lid and the pan to allow air to circulate.
To season a cast iron pan, pre heat your oven to 180 and coat all of the interior and exterior of the pan with melted vege shortening or vege oil. Place the item upside down on the middle rack of your oven and place a piece of foil or a tray on the lower rack to catch any drips. Bake for one hour. Turn the oven off leaving the cookware in the oven to cool. When finished, the cast iron cookware will look slightly brown, but it is seasoned and ready to use. To turn the cookware darker, you may repeat the process two or three times more.
If you get a metallic taste or see signs of rust with your cookware, simply wash with soap and hot water, scour off the rust and re-season.

I wash a new pan well with detergent and water then rinse with hot water well when dry rub with cooking oil and heat it up to smoking hot on the gas ring rinse well and do again then start cooking with it nonstick properties develop with age. Haven't had to do it for ages as they never wear out. I wouldn't be without mine and they come from the warehouse.

Thankyou very much for your info, i will have a go and take a few steaks out of the freezer at the weekend for a treat. thanks again.