What justices on the current court practice which judicial philosophy?
There are, of course, nine justices on the Supreme Court. It is generally safe to say that five of them are conservative and four of them are liberal. The conservatives are more likely to practice the ideologies of strict constructionism and, at times, of judicial restraint. The liberals are more likely to go for loose constructionism and, at times, of judicial activism. It must be noted, though, that conservative justices are relatively willing to be activist in overturning liberal laws while liberal justices are relatively willing to use judicial restraint as a reason to, for example, allow “Obamacare” to stand.
The judicial philosophies are, naturally enough, coincident with the president who nominated the justices. Justices Scalia and Kennedy were nominated by President Reagan. Scalia is the foremost strict constructionist on the court. Kennedy is reliably conservative as well. Justice Thomas was appointed by the first President Bush. He and Scalia essentially have the same philosophy. Justices Alito and Roberts were appointed by the second President Bush.
The liberal justices were nominated by President Clinton and President Obama. They are Justices Ginsburg and Breyer (Clinton appointees) and Sotomayor and Kagan (Obama).