You need to rub the sidestrips down with 320 grit wet n dry first .Then clean the sidestrips , degrease them with some panel wipe or similar .
Next spray the sidestrips with plastic primer . Let it dry and rub them down with some 1500 grit wet n dry .When you happy that its nice n smooth . Clean them again with panel wipe and /or use a tac cloth for the dust .
Now apply the colour coat .4-6 coats should be adeqaute depending how thick you apply the paint .Leave to dry between coats , around 30 mins shouldbe long enough . If your happy with the finish . Now you can apply the lacquer .If the colour coat is not perfect you can rub them down with some 2000 grit wet n dry .
Apply the lacquer , too thin and it will turn out slightly matt finish , too thick and it can run easily and become a little cloudy .Apply 3 or 4 coats , until your happy with the finish .Leave to dry for a good 48 hours . If the finish isn't perfect , rub the lacquer down slightly until smooth .Then you can polish them up with Meguiars scratch X
A couple of tips . If you have a heated shed it would be better , the paint will dry faster .Keep the sidestrips , clean , dust free and dry at all times when your spraying .Get the paint from a local motor factors place that will mix the paint and put it into aerosols for you .