The secret to healthy indoor plants is starting then out right in the first place. You can take these 5 tips for indoor plant care and apply them to exisiting plants that look like they are going to die.

1. Choose the pots.
Indoor plants need to be potted in containers that have one or more holes in the bottom. If your lovely pot doesn't have 1 hole or more in the bottom then the roots will retain too much water  and drown. Your pot could be the killer of your plants. 
You can choose any pot that is suited for your design or budget when you keep the above in mind. 

2. Choose the potting mix.
You can't use the soil from your garden. It could have bugs and weeds in it and also it holds too much moisture for plants that are indoors. Using outdoor garden soil could drown the roots and the soil will kill your plants.

Go to a store near you that sells potting soil. Potting soil contains some great things like peat moss which your plants will love. You can also buy potting soil that has a time-release fertilizer in it 

3. Choose the plants.
When you choose a plant, decide where you want the plant in your home design scheme. If the plant is able to be in the sun most of the time, you would choose a plant that needs lots of sunlight. The same goes for a plant that does well in shade. If the area in your home that you want the plant to sit doesn't have a lot of light then choose a plant that suits that type of environment. The right plant for the right place in  your home.

If you are going to combine a few plants into one pot, make sure they all have the same needs for care. 

4. Prepare the pots.
Before you put the soil in your pot, place something like a small stone or broken piece of pot at the bottom of the pot. This helps stop the soil from going through the hole after you water that plant.
Make sure you have something underneath the pot to catch any water that may filter through. You can buy a tray at the store for this that matches the size of your pot, but to save money, you can use an old plate too. 
 Depending on the size of your pot, put some of the soil in the bottom of the pot. If you have a large plant you may only need a little bit for the roots on the bottom. The roots need some soil underneath them.

5. Potting the plant.
Hopefully, the store where you bought the plant has watered it recently. Before you take your plant out of the container to plant, check if the soil seems dry. If the soil seems dry then water the plant and wait an hour before you put it in it's new home.
Now you're ready to put the plant in the new container. Gently hold the plant at it's base and pull it out of the store container. ( Tip: when the plant is out of the pot, hold the roots ball with your other hand for support) 

Sometimes the roots are all bunched up because the original pot is too small for the roots to spread out. Gently pull at the roots so they come a little more lose. 
You can now put the plant on the top of the potting soil in the new pot. Try to leave an inch around the edges for the roots to be able to grow further. 
Fill the rest of the pot with the potting mixture. Pat the soil down gently. You don't want to pack it down, but just have it settle in the new pot a bit more. Make sure all of the roots and the stem get covered with the potting soil. Only fill the new  pot to about an inch from the top of the new planter.

When you're all done add a bit of water to the new pot. This will help settle the soil and get your new plant to get used to the new container. If the soil settles to less than that one inch from the top, add more potting soil.
And you're done. Time to enjoy your new indoor plants.