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When we laid up sailboats, we would start with a negative mold. we would spray in the gelcoat. Then we would put in a couple of layers of the random mat, then a couple of layers of woven cloth. They said that if we didn't put mat next to the surface, the weave texture of the fabric would start to show through the gelcoat after it sat in the sun for a while. We would only use roving (very coarse unidirectional cloth) on the very thickest pieces.
The cloth was plain weave, prolly the 6 oz.
The mat was that chopped strand mat stuff, prolly about 2 oz.
Since you are working on something smaller, you will prolly want to use lighter weights.
We used rollers to roll the resin into the cloth, and roll the air out. They were prolly 3/4" diameter and 3 inches long.
For resin we used polyester thinned with a little acetone, catalyzed with MEK peroxide. I would suggest that you figure out a way to use ester instead of epoxy, since epoxy is, i think, much more expensive and much harder to work with.
if you use epoxy, find out if there is a way to thin it, or see if you can get lower viscosity grades. if you try to use something that is too thick, it won't roll out well, and the fabric will tend to move around, and it will be too thick, and it will add a lot of weight.
When we needed to fill gaps, we would mix the resin with talc and microballoons, and use less catalyst, since that stuff would tend to really heat up when it kicked.
We eyeballed the volumes of resin, and measured the mek-p with basically plastic shotglasses, oh, there they are, the 1-oz graduated cups. we mixed by pouring the resin back and forth from one container to another, rather than trying to use a stirring tool.
any clothes you could be ruined. we would wear jeans and short sleeves, and wash our hands and arms with acetone. if i were going to do it now, i'd buy a bunch of cheap safety glasses and gloves with gauntlets to try to protect myself, but i'd still get a bunch of acetone for washing tools and such.
if you want it to be strong, then you are really trying to use as little resin as possible. you want the fabric wetted out, but no excess beyond that.
anyway, there are lots of great places to learn about this from people who have done this more recently, so i probably havent told you anything you didn't know. just feeling loquacious today.
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