For learners of Serbian as a foreign language often times it's difficult to pronounce the Serbian sound "LJ" or "Љ" correctly. That's because some students tend to pronounce "L" and then "J" separately. If you'd like to make your pronunciation of "lj" perfect, follow these steps:

1. Try to say "L", as in English word "love". Where is your tongue ? Up or down ?
2. Try to say "J", as in English word "yes". Where is your tongue ? Up or down ?
3. Right, so you noticed that in "L" the tongue is up, just behind your upper  teeth, while with "J", the tongue is down. If you want to say "lj" correctly, the tongue mustn't move from the upward position downwards, because it's one sound.
4. Now, keep your  tongue as if you want to pronounce "J" as in "yes", because it's the right tongue position for the perfect "lj", and at the same time try to pronounce "L", WITHOUT raising your tongue upwards. What happens ? Did you hear your first "lj" ? Now keep practising !

Keep your tongue low, as if you want to pronounce "J" (as in "yes") sound, but say "L" (as in "love")