When I first got Pixie she was very tiny...14 weeks old and 1lb 7oz! the breeder told me to feed her 4 times a day and no more than about a tablespoonful at a time to begin with as her tummy was so tiny and over feeding her would upset her stomach and she would end up with diarrhoea
I was feeding her breakfast at about 7am, scrambled eggs made with a little goats milk and mixed with a little cheese...a drink of warmed goats milk mixed with honey is good too.
Lunch was around midday and was usually freshly cooked chicken..(I would roast a whole chicken then store this in the fridge)
Dinner was around 5pm..Royal Canin Starter or Royal canin Mini Junior..breeder was feeding this so I stuck with it at first..(small kibble great for tiny mouths!) I would mix this with a good quality tinned dog food..(I would buy Royal canin chicken & Rice from my vet) Pixie also liked Butchers tripe mix! stinks...but she loved it!
Then around 9pm I would give her a few pieces of chicken and maybe a drink of warmed goats milk.
I think the key is little and often..this routine worked well for Pixie..
I also see no harm in leaving down a bowl of kibble for your puppy to pick at during the day..a good idea if you are out a few hours day..I do this now with Pixie and she will be be crunching away on her kibble a couple of times a day.