i used to have same problem. saxos are easy the worst car i've owned for jacking
jacking points are too small to jack under then place a stand under. either side of the jacking points is too soft. majority of the rest of the car underneath is too soft or unsafe
figured it out now though. just bought a second trolley jack
for the back:
trolley jack under each of the trailing arm pivot joints, raise them evenly, then axle stands under the jacking points
for the front:
trolley jack under each jacking point then axle stands under where the wishbones bolt to the chassis
i've never had the whole car on 4 stands but if i were to i'd do it as above and in same order. back then front
hope this helps
cheers, chris