Hello to the Poster. I think that if you are really looking for advice on what signs to put up to give you some security against legal action then you need to take advice from either a local lawyer, or your county office.
The folk on here are from all over the world, and none of them are (to my knowledge) specialised Liabilty Lawyers practising over the Internet. So whilst you may receive advice, I don't know how you'll know whether it is sensible advice.
Get up, get going, seize the day. Enjoy the sunshine, the rain, cloudy days, snowstorms, and thunder. Getting on your horse is always worth the effort.