I have always suffered terribly with Hayfever since I was about 16. The last few years I have mostly got on top of it by knowing and understanding what/when my hayfever starts and to begin taking medicine at the right time, increasing when it is at the peak and most importantly taking it even when I don't have symptoms. I can pretty much control the sinus issues with medicine but the eyes is another story. That is what has always affected me the worst and I can't really do much about it.
I take Beconase, (2 sprays in the morning, 1 at midday, 1 at bed), Cetirizine tabs, (1 at morning, 1 at 5ish), Opticrom Eyedrops (same as Beconase but extra drops when it gets bad).
With the eyes I get the mucus membrane becoming stringy which feels like chunks of grit in the eye. It hurts which makes me put my fingers in my eye to try and fish it out which makes it worse but when you get it out it can be instant relief. It's avoiding that situation which makes or breaks hayfever season for me. It can usually be done by not putting my fingers in my eyes to scratch/rub but it is really difficult.
It really puts a downer on the nice weather. I try to just ignore it and it is usually fine when out and about. I find it is going from one environment to another is what kicks off the worst symptoms. Evenings when you want to relax can be a chore and I end up going to bed early because having my eyes shut helps but if I go to bed with symptoms i usually wake up with my eyelids glued together from them streaming in my sleep.