Simeone's men are yet to suffer defeat as they bid to retain the Spanish title, taking eight points from their first four games.
However, Atletico's defence has been fragile in their last two games as they lost 3-2 to Olympiacos in the UEFA Champions League and were held to a 2-2 draw by Celta Vigo last Saturday.
Atletico conceded just 26 goals in the league last term on their way to a first top-flight crown since 1996, so their vulnerability at the back in the last week came as a surprise.
Simeone - who is serving an eight-game touchline ban - is keen to ensure that his side cut out the mistakes against an Almeria team that claimed a 2-1 win at Real Sociedad last weekend.
"There are aspects of our game that we need to improve as a team," Simeone said.
"When you concede, that is usually as a result of a team's mistake. It can be an individual mistake but if the team is strong you can compensate for that and stop conceding. Obviously, the less you concede the better. I hope that we can go back to clean sheets.
"We will find a dangerous rival [Almeria] which have improved from last season and are stronger.
"Their players are very quick and [forward Fernando] Soriano is very good in the air, so we will have to focus a lot on defence. It will be a difficult match."