Here are a couple of tried and tested tips for tying ties. Apologies for the excessive alliteration.
I’m a fan of a nice, large dimple in a tie. Two reasons: I think it adds a certain lustre to the silk to be pulled in thus, and the added tension helps keep the tie in place, taut and a little pushed out.

I’m sure most are familiar with how, basically, to achieve a dimple (if not, please inform me in the comments section and I’ll do my best to describe it). However, I always found difficulty in achieving a consistent dimple in the middle of the tie. It would always verge over the one side and eventually, as a result, disappear. I also found that a decent dimple in the early stages of tying would seem to disappear in a similar way by the time it was tightened up to the collar.

So, two tips. First, lay out your tie on a flat, hard surface and estimate the two or three inches that pass through the knot during tying (perhaps hold it up to your body to discover this). Then, fold the tie along these two or three inches in half, with the front of the tie on the inside. Press gently along the fold with your fingers, or leave a heavy object on it briefly.

When you pick the tie back up again, there will be a visible fold down the blade. That will fade after a short while, but the lining of tie retains the fold. Because it is often a thinner silk or a canvas, it is more easily distorted. So when you next pull the tie taut, it will naturally return to that halfway fold, creating a perfectly placed dimple. The effect is also reinforced over time – the more a tie is tied with that dimple, the more easily it will return to it.

Second tip: always secure the knot and its dimple completely before pulling on the thinner blade to bring it up to the collar. Otherwise the dimple is likely to be loosened on the way up.

When you have pulled the wider blade under, over and down through the knot, let it hang for a second to pinch it ready to create the dimple. Then tighten the knot by pulling both the wider blade and the knot downwards – it is slightly counter intuitive to pull the knot down, as it will eventually go up again, but pulling it down thus will tighten it far better for the journey up to the collar.

One more tip, even though it does bring the total to three and spoil the alliteration: if your knot is a little too thin for your liking, try looping the wider blade over once more (in a four-in-hand knot this is) than usual. It makes less difference than you’d think, but just enough to satisfy.