Tietjens' side will take on defending series champions Fiji and Wales and Canada in pool play.
Fiji lost to South Africa in the Dubai sevens semi-finals last week while Wales and Canada had disappointing tournaments.
Samoa finished in sixth place and look to have made improvements from last season.
But Tietjens said he expects their group to provide stiff opposition.
"Canada is going to to be really tough, they are disappointed with their last tournament. Obviously they will want to get a few points on the board."
"Also Wales, because on any day both those teams, and we saw Canada win a tournament last year, they can beat any team. You have got to be up for every game. I have always said as a coach that to win a tournament you have to win six finals and our first final is against Canada," he said.
Tietjens said he's maintaining his goal of finishing in top eight of every tournament.
"Success for this tournament to me is being consistent, getting back into that quarterfinal group and getting back into that top eight."