How to make my scrambled eggs more yellow?

Ah, we consumers and our expectations:
Egg yolks are yellow.

But in reality, yolks come in a range from pale yellow to deep orange. The colour is determined by the food (wheat makes lighter yolks than corn, for example) and can be influenced by feeding "colourants" for a darker hue. Some regions allow even artificial dyes, but a pinch of paprika will do nicely. Apparently the "expected" or "preferred" yolk colour is also a cultural thing, I found a source claiming that European customers want more orange hues while US customers expect deep yellow.

Organic and free-range eggs typically have a greater variation than those from large agro-industrial production.

So if your scrambled eggs are sometimes lighter, sometimes darker, either accept it as "natural" or check the colour of your yolks when you crack the eggs and for pale yolks add a colourant like a small pinch of

• turmeric (what makes curry powder yellow) or
• paprika (for more orange eggs).

If you use only a very small amount, it won't influence the taste or only very slightly so. Stir the spice in, then proceed as usual.

With my experience, Normally red shell eggs' yolks are yellower than white shell ones.

In Sri Lanka, the domestic hens lay orange yolk eggs. Yolk colour depends on the food that hen consumes.

I have noticed the eggs from my local farm-market, and more generally, free range eggs, tend to have yellower yolks, sometimes even orange ones (which are very tasty). Yolk with deeper color should produce scrambled eggs with deeper, warmer color.

I do not claim this is a guarantee, by any means, it's what I have seen but that's not proof but simple correlation. The hen's diet is supposed to have an effect on color, as seen in this question and this one, but other living conditions or separate factors like breed might well play a role.

What I would recommend is, if you keep a rough track of which eggs you buy - especially since sometimes you get ones with good color and sometimes not - and try out different options like size, color, free range, organic (all depending on availability), you might see if some brand tends towards the brighter color as you prefer. At that point you can preferentially buy the one that works best for you. Or else you might find that, I don't know, the color matters more than brand, or which season the eggs were laid in makes is noticeable.

And if you find yourself with eggs that are pale for whatever reason, take Stephie's answer and look into yellowing spices like turmeric or paprika for a bit of extra brightness.

The fresher the egg, the more orange the yolk. As the egg ages, the whites get milky and the yolk a pale yellow. Buy farm fresh eggs at a farmers market if possible. We have our own chickens so we only cook with fresh eggs.
Perfect scrambled eggs: Whisk eggs together, add a pinch of salt per egg. Put scrambled eggs in a cold pan, put heat on medium and whisk/stir eggs in pan the entire cooking time start to finish. As the eggs begin to set, turn heat to lowest setting and continue to stir. I raise the pan off the heat if eggs seem to setting to fast. It should take about 10 min to cook the eggs. Add nothing else and serve. You will be shocked how creamy the eggs taste. The pan is tough to clean but worth it!