Earn More Stars

The most commonly asked questions are:

1. How to I increase my score so that I can get through a level with at least one Star?
2. How do I get my score up so I can get 3 stars on each level? 
Here is the description and Instructions as per King.com

The three witches are looking for a new addition to their circle. You have been invited to their haunted house to prove your worth. Can you create enough spiders and keep the cauldron bubbling?
  1. Aim and shoot with the mouse. Match 3 of the same colour to remove them.
  2. Every shot that bursts bubbles will add a new spider. If you don't burst bubbles, two spiders are removed.
  3. The score for the falling bubbles increase every time they bounce on a spider.
Sound simple enough? LOL
Ok, the more points thing.... These are the things you need to remember:

Balls bouncing on Spiders are worth MORE than straight shooting them.

 - You create spiders by shooting a 3 ball or more combinations.
 -You get gold spiders by bursting balls 3 times in a row.
 - Green spiders make your balls multiply when they bounce on them. Get Green spiders by bursting ball combinations 5 times in a row.
 -If you have 10 gold spiders you can't get a green one.
 -If you're nearly ready to drop the ceiling and have enough balls left you can miss 2 shots so you lose 4 gold spiders. The spiders will come back one by one as blue ones and of the four you lost one will come back green. Make sure you use the missed shots to make pairs so you have enough to not miss any for at LEAST 5 shots to get your greenie.
Then you can drop the ceiling.
Thanks to Belle M Smith for help with this.

How can I make sure I shoot 3 ball combos 5 times in a row?

ALWAYS line up your next shot. Think to yourself, if I shoot this green, will I then be able to shoot the red that is in the cauldron? You don’t want to miss a 3 bubble combo or you will lose spiders.
Always remember, falling balls are worth much more than balls that are shot. Keep as many spiders at the bottom as you can by never missing. Never miss by always lining up your next shot.
With the Colour changes you have to think even more… Right now that cluster is Red and I have a red ball, so, I will switch it to the blue, shoot over there and then shoot those reds once they have turned gold…
Make sense?

The next thing, don't always take the EASY hit.

If 2 balls are close to a wall you can drop a bunch if you shoot the two that are holding them up.
See Example picture

See the 2 Reds that the pointer is pointing to? If you hit those you will drop that side.
The easy shot is to the left. That is what I mean, the EASY shot is not always the BEST shot.
Now once I clear that side I then have a WALL that I can bounce balls off to clear out the middle, other side or ceiling if I want, depending on what I need. If it is one of those levels where you can't see the ceiling, then concentrate on clearing the lower ones. This is made a LOT easier if you can side shot.

Don't be so focused on shooting 2 ball clusters to make 3 that you miss a GAP oportunity.
In the example pic below, you will see I have a BLUE ball ready to shoot and instead of shooting at either side, I shoot right in the middle.
Now the Gold is taking up the ceiling and I have both Blue and Gold in my pot. Why would I shoot the Blue and not the gold?
So I can get another spider dangling before I drop the ceiling.....
Remember, 3 ball hits = spiders, Balls bouncing on spiders = more points.
NOTE: Not all GAPS are this easy to see. The gaps can also be just one ball either side, or they can be angeled, and you don't think about it because they are not together... Just remember to keep a look out for things like this.

And remember,  
Just dont rush levels. Thats the GREAT thing about this game. Its not timed. You can walk away mid game to make a coffee and come back and sit and think.
Most of the time I hit a bomb and go "Oh no I have to hurry up and clear a path!" You don't. The bomb ONLY ticks down by the number of shots you make so go and have a coffee then look again. You'd be surprised the shots you can see with fresh eyes.