Wales coach Osian Roberts has urged the players to "stay grounded" after their victory over Belgium.
Chris Coleman's men top Group B of Euro 2016 qualifying after their 1-0 win over Marc Wilmots' team last Friday.
Wales, who have not qualified for the finals of a major tournament since the 1958 World Cup, have a three-point lead with four matches left to play.
"We need to build on what we've done so far and not assume we've done anything yet," said Roberts.
"We can't afford to take one eye off the challenge that we've got ahead of us, and we'll make sure that everyone stays grounded and we focus on that task."
Wales visit Cyprus on 3 September, before hosting Israel three days later. Coleman's side finish their campaign with a trip to Bosnia on 10 October and the visit of Andorra three days later.
Wales have a five-point cushion over third-placed Israel, with the top two teams in the group qualifying automatically for next year's finals in France.
Coleman's side have already beaten their next two opponents in this qualifying campaign, part of the run that is set to propel them into the top 10 of Fifa's world rankings for the first time.
"We have to respect the opponents in the group," said Roberts. "It's always more difficult playing against a team second time around.
"We've laid a great foundation. Things couldn't have gone much better.
"But we also know the most important games are ahead of us and we have to get those right."