Method 1: Go to misty marsh upper left in the portal they should take u to heart lake. Once in heart lake take the portals to the left try each one until u get to icy
Method 2: if ur lvl 50+ take 50k with u, talk to cronus teleporter lady (NOT Island teleporter, regular tele) and ask about island. From island tele to icy.
Method 3: If above lvl 70 talk to island teleporter in cronus (near mentor lady) to take u to island with 30k gold. At island tele to icy.
Method 3: folow this: