My problem was trying to surprise her (since she insisted she wanted it to be a surprise) but at the same time she knew that it would be coming some time soon since we had discussed it. this led to 2 options.

a) put the finger on her while she was asleep, and then explain to her as she woke up that "I'm glad you found last night was the most memorable experience in your life and that you said yes"... and see her reaction. or

b) Try and book a surprise trip away but disguise it as something else.

As is i went for b though rivrmeadream def would have wanted me to go for a. we had gone to liverpool for a few nights to visit my friends, then i told her we'd stop off at a pub for lunch on the way home (since it was also roughly our anniversary). But when we got there i explained that lunch was a lie and that i had booked a room for the night adn a meal (again to celebrate our anniversary) (for those interested it was at the "Crown at Whitebrook" in South Wales, which is a michelin star restaurant, so was a very nice place).

I kept up the pretence that it was for our anniversary and got the staff in on it too, had a really awesome meal, and got one of the staff to spread rose petals around the hotel room while we were eating (puking emoticon), she thought if i was going to propose that i would do it in the restaurant but left it till back at the room, she walked in, exclaimed "oh wow look at this" then by the time she had turned around i was on one knee and asked her.