Time managing and world speed

Depending on your activity some worlds will suit better for you. As a general rule:
Slow worlds for people who log few times per day.
Fast worlds for people who log every hour per day.

The content is based on the grepolis en forum: here

World speed 1:
The Cons:

• This is a very slow moving game speed, good for people who can log one time per day;
• You can log on in the morning and place something in the queue and when you arrive from the work it will still be there;
• You must be very careful with your armies, otherwise it will take weeks or a month to be rebuilt.

The Pros:

• This speed is almost certainly suited to the less active player;
• There may be less fighting, but when it does happen, it is HUGE;

World speed 3:
The Cons:

• You must be 24/7, things happens too fast;
• Armies can be built in 2 days;
• Most of the top players are going to be very active and if you're not, then your cities are just food for them.

The Pros:

• You'll always have fun;
• The players that are active are truly awesome. Most speed 3 players are very knowledgeable of the game due to the amount of time they must spend playing it;
• Active players receive many rewards, because of the "inactives".

World Speed 2:
The Cons:

• You'll struggle with some buildings taking 12 hours to be finished;
• Sometimes you may fell it could be faster or slower.

The Pros:

• You can play regularly without worrying about daily attacks;
• Still a moderately fast pace world speed;
• Basically a really good speed for the not so active but still serious player.

Time managing

The best way to play grepolis without spending too much time is using the premiums, unluckly. It may be contrversial but I believe that everybody can buy 20000 coins at once, one time per year, only spending to use the councils and swaping heroes and opening more slots in the inventory. 

After that, learn to use all the tools of the Administrator and the Captain, it will save a lot of time.

Tips:

• Don't take more than 5 farming villages and avoid taking them in different islands;
• Focus in recruting units in one or two cities, sending resources to them and completing their training queue;
• After some time, farming cites can be something really boring if you have a lot of OLU cities. Then, for example, you can send stone from your LS cities(they use more wood and silver) to your slinger cities and send wood from your hoplite cities to your LS cities.
• When you get a lot of cities like more than 20, it's wise to divide them in more groups, even if they are the same type.

Any doubts post in the comments.