5 months is still a bit early for solids. Is there some pressing reason you need to start now? (Most sources recommend waiting until 6 months unless baby clearly needs them a bit earlier.)
Regardless -- bottle first, and then solids. And you'll only be offering solids once a day at first. It doesn't matter when, though it's sensible to not start at bedtime -- if she has a bad reaction she'll be up all night. (And so will you.) Also, most babies fall asleep while being nursed/bottle-fed at bedtime, so you don't want to wake her by sticking her in a high chair at that point.
So continue to give bottles in whatever pattern/schedule you've been doing. After one bottle, put her in a high chair and offer a small amount of solid food. (Doesn't matter what -- it's traditional to start with rice cereal, but you can give fruits or veggies if you prefer or she likes them better.) A teaspoon or so is a sensible first meal. If she opens her mouth for the food, eats it, enjoys it, and has no bad reaction, you can offer a bit more tomorrow. Gradually increase as she enjoys.After a week or two (depending on her interest) you could add a second solid meal, but she probably won't need 3 meals a day until around 9-12 months. You want to be sure that she isn't taking so many solids that she cuts back on her milk -- the formula is still the basis of her diet; solids are mostly 'just for fun' for the next few months.
If she won't open her mouth or spits/pushes the food out, you can try again tomorrow. If it's still no-go, wait a week or so before trying again. There's no rush.
Remember that it's just for fun, so keep it fun.
EDIT: Do NOT put cereal in his bottle. (As another poster suggested.) If baby can't sit up and eat from a spoon, baby isnt' ready for solids. Period.