my girl is 7 1/2 months now and has been on sol...

my girl is 7 1/2 months now and has been on solids since 5 1/2 months or so. the problem is she is not really that interested most of the time and would rather have her bottles!!! she gets very fussy and clamps her mouth shut if she is not interested!! how do i get her to take the solids over the milk more frequently??? any help greatly appreciated!! her brother is 9 now and i can't remember a thing!!!