They are all easy to make. I'll give you some ideas about free patterns that work for a small baby (though not that small!)
Read on for more information and ideas.
Before Ada had been born, I had bought a set of five onesies from Tu at Sainsburys. These were size 3-6 months. I loved the colour combinations. Little did I realise how quickly she'd be wearing them.
I wanted to make them into 'outfits', and I found a couple of pretty fabrics in a similar colour scheme.
The first, floral pattern was only a fat quarter, so I could barely get a fully circular skirt out of it. To find out how I did it, read this post. I thought this would just about do for 3-6 months (short and cute) which was the size of the onesies.
It looks very nice with the turquoise-y striped onesie.
The other fabric had little wigwams and feathery spears. For this, I used the See Kate Sew Easy Baby Dress free pdf pattern and tutorial, which is a 3-6 month pattern. It is, as it says, pretty easy, and has the advantage of elasticated straps, so it can fit for a few more weeks than one with plain straps.
In the picture below, it is worn with the apricot onesie. Does it look a smidgen large? Well, maybe, but Ada was only 12 days old! This 3-6 months dress won't fit her for very long though. Thank goodness I didn't make it in newborn or 0-3 months.
Next, the first size leggings Mummy had bought Ada already didn't reach her ankles, so I had a go at making her some new leggings, recycled from an adult ribbed vest. I used the free PDF and tutorial from Andreas Notebook, in 3-6 months. (It also comes in 6-9 months and 9-12 month sizes.) I had a couple of small lengths of some pale blue elastic lace which I used to trim the bottoms of the legs. More information about recycling leggings from an adult vest here. They fit her well, at 6 weeks.
Well, I've talked above about the need to avoid first size clothes for a newborn baby. The ones above, I've managed to salvage, either by starting with a larger size, or re-making. Sadly though, there are others that failed, and will be going to a hospital charity. However, if you are still determined to make tiny baby clothes, you can read about these projects here. But don't say I didn't warn you!
(This last one I like so much I may have a go at remaking it with different straps. I'll be sure to blog about it if I do.)