I breastfed my first child until 14 months and my second until 20 months. My first was really easy to wean, as I was pregnant and he self-weaned around the time that they say the milk changes flavor, etc. We had one feeding left at that age and it was during the night. He stopped waking up for the feeding and the first time he did wake up in four nights, I just refused to feed him, as he hadn't had it in the last four nights, so I didn't think he needed to start again.
With my daughter, I gradually weaned throughout the day at about 15 months. She was down to one feeding before bed by 18 months. She was not going to wean herself and I was ready when she got to 20 months, as she still needed to breastfeed to be comforted and I felt uncomfortable doing that in public. So, on Jan. 1st of 2007, she had her last feeding. It was my New Year's resolution and I just bit the bullet and refused to feed her. I rocked her, cuddled her and all the while told her that there was no more, "booboo." She cried herself to sleep the first few nights, but with the help of a pacifier she grew accustomed to the idea. She only had the pacifier for about two more months and then she was done. Not too terrible, but she was definitely harder.
I say to follow her cues on which feeding to eliminate first. Just do one at a time and keep her busy doing something else at the regular feeding time. Read her books, sing to her, color, etc. She will become distracted and into her activity that she won't even know she missed a feeding. I hope this helps.