How can I earn a lot of coins early in Fifa 16?

Easy way to earn coins.

1. Be an above average Fifa player, this is best done by playing career mode on Legendary.
2. Play FUT TOTW Matches on Legendary and Win
3. Play FUT Seasons
4. Use coin Boosts only after reaching Div 4 or Higher.
5. Buy World Class players if they get an inForm, for example: if say, Poga gets an inForm TOTW, his regular Rare Gold Card will decrease in value for a short period.
6. Buy on Market Crashes

see this link

Since FIFA 2013 I have found the following method the best way to earn coins:

Play online league matches

You will start off in the lower leagues and therefore paired with inexperienced or bad players. Your initial squad will also be sufficient in getting you through a handful of matches before needing to pick up new players and/or contracts.

You will earn coins for each and every game you play... win or lose. Never quit out because you are losing. The coin difference between a win and a loss isn't that great (as other factors than result also affect the coins given).

It goes without saying that the more you play the better you should get. As you climb the leagues the end of season rewards will increase. If you are struggling (connection issues, not enjoying the skill level of opponents) you can play single player leagues.

Regardless of single player or online mode, you may find a certain division easy to win. You can win the division, then in the following year lose all your games on purpose (using cheap bronze players to fill the squad). Keep cycling the promotion/relegation between 2 divisions to build up a stockpile of coins.

Following this method (plus the extras you have in the OP) you will be able to put together a decent all gold squad in no time, and have surplus coins to keep the contracts renewed. Remember that silver packs are usually pretty cost effective ways of picking up contracts for gold players. Always sell off what you don't use (basing prices off judgement and standard market prices). Quick sell items that you cannot sell off in the market.

It is possible play the market but this varies over time. If you have the time you could pick up last minute bargains, such as a gold player for 300-400 coins. Immediately re-list the player for a small profit (e.g. 500 coins). It is generally a lot of effort to do this (I doubt it would be any faster than just playing a game). However, you may find that picking up gold players for 300-500 coins to replace your current out of contract players value for money. New players default to 7 game contracts (double check what you are buying, as the seller may have used them in some games beforehand). You may get lucky and find an 80 rated player for under 500 coins, with a 99 game contract!

That should be enough to get you started. You can easily build up a small fortune to pick up the top players as you play more games.

Update

The key difference with regards to previous releases is the new Draft Mode. If you are a capable player I suggest investing in the 15k buy-in. You are given a randomly generated top squad for a 4 round knockout tournament. Once you are knocked out you will be given a collection of random packs. It appears that the further into the tournament, the better the packs. A first round knockout often gives 2 gold packs and a silver pack. Selling off most of these cards should at least cover half the cost for a first round knockout. However, later rounds = better packs. These yield rare, top rated players. You can choose whether to keep the players or sell them off.

The way I am slowly earning some cash is by buying bronze booster packs (400 coins) and selling the 55+ players, the contracts and the healing and fitness cards. EDIT: I quick-sell the others as they tend to sell not at all or extremely slow.

Contracts, healing and fitness usually go for just 150-200, but you will get around 4 in each pack. Meaning you have already made some profit on them.

The 55-60 players go for 150-200 and 60+ can go for up to 350-400 but generally I just list them for 250 or 300. I kept a list of sales and I make around 700 coins profit per pack. It's not a lot, but it's a reasonably steady income without much effort.

After a short while I began to experiment with the 2500 coin silver packs. On them too, I make 700+ profit per pack on average.

It's not quick-cash, but it's easy cash that do not require you to play the game. For instance use the web-app or the mobile app like I do.

I made quite a few coins (40.000 approximately) on buying and selling players, but then the prices dropped a bit and now I refrain from that. This method might get you faster coins in the long run (when you have some more to spend), but also requires more attention than buying the booster packs.

Of course buying the coin boosts is also an useful way, but again require you to actually play.

Hope this helps you out a bit.