We purchased a Star shaped metal Candle mould recently, but we found it very difficult to take out the candle from the mould without damaging the shape. So, I have decided to make a Silicone Candle mould using the Star shaped mould as base, which you can see in the above picture

Please see the step-by-step instructable below on How to Make a Silicone Mould from existing objects

Step 1: Attach Metal Mould to Board

First we need a base for fixing the metal mould without disturbance.
Here I have used a small piece of plywood and attached star mould to the base with Hot Glue on all sides

Step 2: Cover the Mould

We need something to cover outside the mould. The cover should have space enough on all sides of star mould and should also be flexible enough so that we can take out afterwards. I found a suitable plastic water bottle lying at home.

First cut and remove the bottom portion, then measure the height with reference to the metal mould
Cut and remove the neck portion of bottle. Now the plastic bottle can be placed over the metal mould to cover it on all sides

Step 3: Split Plastic Bottle

Split the plastic bottle vertically and attach it again with insulation tape or Duct tape.This will help us remove the plastic casing once the mould is cured

Step 4: Attach Plastic Bottle

Apply coconut oil lightly inside the plastic bottle and the outer surface of the metal mould
Place the prepared plastic bottle in position and attach it with the metal mould with glue gun
I have also inserted a piece of star shaped candle inside the mould to prevent silicone material to seep inside mould

Step 5: Prepare Silicone Mould Making Material

The Silicone mould making material consists of two parts, the Base and the Hardener. I got one kilogram of Silicone Base with suitable amount of Hardener included.
I have roughly calculated that I need about 500 grams of Silicone mix for casting the mould
Take 500 grams of Base in a container and add half the quantity of Hardener to it
Mix with a stick thoroughly so that both Base and Hardener mixes well without any air pockets

Step 6: Pour Over Mould

Once the Silicone mix is done, pour slowly at the center of the metal mould.
Allow the silicone material to flow freely through sides so that no air is trapped with the mix
Once the mould is filled to top, keep it in a shaded place without disturbance for the silicone casting to cure

Step 7: Remove Plastic Covering

The silicone material I have used will be fully cured in about 24 hours
After 24 hours lightly touch the top of exposed silicone material
If it is still not fully cured allow more time. Once it feels hard, you can remove the mould from plastic covering
Remove the Insulation tap and hot glue from the bottom
Peel off the plastic bottle from Silicone mould