Dont bring with you memories of a past poor workout or lagging negativity about missing a new PR your last workout. Go through the motions of your workout. Load the bar or pick up the dumbbells or grip the handles. Choose your weapon that you will use to destroy the mental blocks that you have set up for yourself in the past. Perfect form, perfect execution you nailed it and focus for a few minutes on how great that feels.
Visualization is only one ingredient in the recipe of mental preparation.
You have to take that vision and make it a reality. Do exactly that when you enter whatever pain domain you call your gym. Refuse to believe any misconception, myth, stereotype and down right CRAP that you ever grew up believing about women and lifting about women and anything for that matter. Get mental when you hear anything remotely similar to that and use that frustration to fuel your workouts. Use those comments as a challenge to prove them wrong.