It is A LOT better if you do it yourself. That is of course if you do it correctly.
Automated workers are very dumb.
Your goal is to have every tile that you are using fully improved. That means you will need to have a lot of workers and use them efficiently. the amount of workers needed is hard to say, but 99% of the players build to few of them, so you can safely assume you are among those.
For using them efficiently, try to minimize the waste of worker turns and start by doing the jobs that give most benefit per worker turn.
Wasting worker turns happens when you:
-press spacebar and not use your worker one turn
-move a worker on an unroaded tile (thus try not to use stacks of workers on not yet roaded tiles as every worker will waste a turn whereas if you use one worker to first road it, only 1 turn is wasted)
-using turns to travel between jobs. Best is if you can start the next job on a tile connected by roads and no more than 2 tiles away. So you can start the job the same turn you finished the last one. Often of course, you will be moving to a bare unroaded tile, so 1 turn loss is usually unavoidable. Try not to make it more than 1 though.
-workign a tile but not roading it. If you do this, you will need to waste a turn by moving on an unroaded tile next time again to road it.
-doing unneeded jobs. working mountain tiles for example is usually very unneeded in early game.
-roading forest/jungle tiles that you are later gonna cut. roading forests takes longer than grassland, so first cut the tiles, then road them.
In despotism, irrigating grassland is useless. It is best to try and have 2 food from every tile unless it has a bonus and can produce more. That means, you will irrigate plains and mine grassland. Since irrigating takes less time, it is better to first irrigate plains, then mine grassland (unless you have bonus grasslands which have priority of course).
Also mining hills is not a job for early in the game since in despotism it will only produce 2 shields anyway.
Many people use their workers inefficiently (stacking and longer than 1 turn travel times) because they say that way they can make a tile improved faster and thus they would win some production from that tile. However, by using your workers less efficient, you will always be running behind your needs for improvements. Try to work as efficiently as possible and have enough workers to have your tiles improved already by the time you are gonna need them (due to your city growing and thus needing a new tile for the next citizen)
In early game, when you have just 2, 3 or 4 cities, it is not yet reasonably possible to have all used tiles fully improved. Therefore, in early game it is more allowable to work less effient if that way you can get for example a settler 1 turn faster.
Also in early game, commerce means nothing, food and production mean everything. Therefore, you might for your first or second city sometimes skip a road and just mine/irrigate them in order to get your settler factory going faster. After those first 2 cities, never have a worker leave a tile if it is not roaded yet.
For the same reason of commerce maning nothing, in early game when you are gonna road+mine/irrigate a tile, first do the mining/irrigating, then the roads.
Later in the game, when i am working ahead of my needs, i usually first build roads. This improves your flexibility as then you can if you want move extra workers on the tile for the mining job without wasting turns (if the extra workers are within 2 tiles and thus can start working right away)
Thats the most important things about workers that i can think of now
