Anniversary ideas

Take her to a nice restaurant or cook something nice to her. If you suck at cooking, order a takeout and have a nice meal at home with her, spend some time with her and give your attention to her. If she likes gifts, get her something she likes or the opposite, what she'd never expect. Something special, romantic and what she would definately like. Some flowers would be nice and maybe to make a nice romantic mood, add some candles and few flowers which she likes the most. Roses are the most confident way to go. If she doesn't dig those, just tell her you didn't either know what to pick or whatnot.

Everything else is in your own hands.