Rock bottom Villa are seemingly heading for relegation having won only three Barclays Premier League games all season.
Swansea would take a huge step towards securing their own safety by completing a season's double at the Liberty Stadium, but Guidolin has stressed the dangers of complacency against Villa opponents who have lost their last five games
"Maybe this is the most important game of the season and we only have to be focused on Saturday," said Guidolin.
"Only the present is important, the match against Aston Villa, not the future.
"It will not be easy. I know this situation because I have many matches behind me and know how difficult a match like this is.
"My team has to play well with concentration and intensity, as if it is a final."
Swansea are eight points clear of the relegation zone with first-team coach Alan Curtis overseeing a mini-revival with wins over Arsenal and Norwich when Guidolin was absent with a chest infection.
Guidolin will be back in the dugout for Villa's visit after missing the last three matches, and he feels Gylfi Sigurdsson holds the key to Swansea completing their rescue act.
The Icelandic playmaker has been Swansea's stand-out player since the turn of the year and has scored scored seven times in his last 11 games.
Asked about Sigurdsson's form, Guidolin joked: "I hope he has a good feeling for me.
"No, we have a good feeling together, but he has confidence and knows he is an important player for us.
"He is a midfielder or number 10 with many qualities.
"I said three or four weeks ago he can score 15 goals in a season because he is very clever and can play in all positions in the last 30 metres."
Victory would take Swansea to 36 points and within four of the magic 40 mark, which is generally regarded as the total required to secure top-flight status.
And defender Neil Taylor accepts the magnitude of the fixture given the two clubs' league positions.
"The build-up will be pretty much like the Norwich game," Taylor told the South Wales Evening Post
"We've got a match against a side that are down there, so they're a direct opponent.
"This is my most difficult season here because we haven't experienced this [relegation battle] before.
"We've always been mid-table or thereabouts at this time of year - we've tended to be pretty safe.
"But let's just see what happens.
"There are still eight games to go so it's too early to be making judgements about the season."
Source: PA