Thanos originally obtains the Power Stone on Xandar which makes some sort of sense, the Power Stone gives great, ahem, power to which he can more easily attack his opponents to get the other Infinity Stones. He then goes to get the Space Stone at the start of Avengers: Infinity War from Loki which again makes sense because it gives him the power to teleport to where he needs to be. Arguably he is now in a position to overthrow anyone he needs to with these two powerful Infinity Stones as Banner says.
Bruce Banner: No telling. He has the Power and Space Stones, that already makes him the strongest creature in the whole universe. If he gets his hands, on all six Stones, Tony...
Avengers: Infinity War
Thanos then dispatches his children to get the Time and Mind Stones from Earth whilst he goes to get the Reality and Soul Stones. Which makes some sense, he knew he could easily get the Reality Stone from the Collector and probably assumed it would lure Gamora in so he could get the location of the Soul Stone from her. All here works as planned.
Lastly, though he needs to get the Time and Mind Stones as his children failed him. Had everything gone to plan he have gotten the two Stones from them and put them in the Infinity Gauntlet. However, only the Time Stone is there and so that is the one he places in next. We can't know if this was intended or he just put it there because that was the order he got it in as he was hoping to have both at the same time.
In short he appears to get the Infinity Stones in the logical order for gathering them with the resources at his disposal... had everything gone to plan. However, because it doesn't go exactly to plan it has to change and so there's not really a specific order, only what makes sense to him at the time. Note he knows that the Avengers on Earth are probably expecting him so sending his Children there whilst he goes to collect the other Stones also makes sense as he is hiding in the shadows for longer.
Lastly, note that the Infinity Stone in the comics do not match to the positions in the MCU so if we take that as some sort of evidence we can see that it might not matter at all.