Bring milk to a boil stirring now and then.
When hot pour the lemon juice and stir, milk should start curdling.
If it doesn't happen add some more lemon juice.
When milk will be completely curdled you should see greenish colored whey with lumps of cheese in it.
Put in the sink a colander, cover it with the cheese cloth and pour immediately the curdled milk.
Gather the edges of the cloth ( pay attention as the liquid is very hot!) and squeeze exceeding water.
Put again the paneer into the colander with the cheese cloth and put a weight on it.
Let it drain for about 40 minutes then take it off the cloth.
You can cut it in cubes and use it for your Indian recipes or you can eat it plain.
You can store it in fridge in an airtight box for 2-3 days.