Poom returned to his native Estonia after retiring in 2009 and is currently working for FC Flora Tallinn.
"Simon Mignolet, I don't know him so well but from what I have seen of him he looks good and has everything going for him," Poom told safc.com.
"He's got good presence and he has been playing really well. He's got a big future ahead of him.
"The advice I would give to him would be to enjoy what he's doing and work hard, not rest on his laurels and keep doing what he's doing.
"He needs to stay focused on what he wants to achieve and, most of all, enjoy it."