Tips to Use Lycan (Dota2)

• Wolves can be used to scout runes at the beginning of the match and during the laning phase to avoid losing gold and experience.

• Always Summon Wolves in base when going out to jungle for the first time (at about the 0-10 second mark) since the wolves are fast enough that you can get a creep camp killed without using any mana.

• When taking on Roshan, it is advised to use a Smoke of Deceit to avoid being spotted by enemy observer wards. Teams facing a Lycan will do their best to prevent early Roshan kills by planting observer wards near the pit; given that a detected Lycan is easy prey while doing battle with Roshan, slipping past those wards will do wonders for his lifespan.

• Nature's Prophet has great synergy with Lycan, for several reasons. Howl can drastically increase the combat effectiveness of Treants by boosting their damage potential. This same advantage can also aid in handling Roshan, allowing boosted Treants to tank him instead of Lycan. Nature's Prophet is (like Lycan) a jungling and laning hero, so his absence while fighting Roshan is not a great concern for his teammates. Finally, the Prophet's ability to teleport directly into Roshan's pit is also useful for avoiding enemy wards (using Nature's Call in Roshan's Pit with Sprout is advised, however, in order to remain undetected by said wards).

• At level 8, with items like Vladmir's Offering and Power Treads or Medallion of Courage, Lycan can solo Roshan. Summon your Wolves and tank them alternately with the hero, but not let them die until re-summon is ready. Keep Shapeshift just in case the enemy comes for you, so you can escape.

• Shapeshift is a very strong and versatile Ultimate to use. When activated, it gives Lycan hasted movement speed, allowing a great deal of maneuverability in battle to chase down fleeing heroes or to escape from potentially dangerous areas. While Shapeshifted, you are immune to every Slow, including Hex, Purge and Slow Ultimates like Epicenter, Freezing Field, and Primal Roar (though if directly targeted by Primal Roar, the stun is still applied). 

source: http://dota2.gamepedia.com/Lycan