Don't raise your hopes.Very few cases that counsel do result in counsel thinking there are grounds of appeal.Most of those are appeals against sentence only.Counsel expects to lose about half the trials they do,so there's no shortage of guilty verdicts to think about!
Counsel will be looking for mistakes of law, 'misdirections', in what the judge told the jury in his summing up at the end of the trial. As counsel always takes a careful note of what the directions are, and as he has the opportunity to invite the judge to correct any false impression or apparent misdirection given (rather than risk a guilty verdict as a result), he will know if any misdirection remains and be quick to advise appeal..The other area is the admission of evidence in the trial which should not have been admitted.Counsel will know all about that too, and have an opinion about it and whether it made a difference, because he'll have argued against it in the trial or, if it arises by surprise, moved that the trial be stopped and the jury discharged.
Even if leave is given, there's another obstacle.The Court of Appeal may 'apply the proviso' that is agree with counsel but rule that the jury would have reached the same verdict had the evidence not gone in or the misdirection not been made, because the case was overwhelming and the error not such as to result in injustice.