I've asked for consent for the first time with every partner and they have all found it hot. Ive come to find out later that they all really appreciated it since their previous partners just went for it. The trick is not to be a awkward in delivery or overthink it. stay in the moment. A simple "do you want to fuck?" has worked great for me. Make sure you're both turned on and ready to go and just say it. You can segway into it with some minor dirty talk too. If you're not comfortable with that another one I've used when I wasn't sure about birth control is "should i grab a condom"? Since I have to figure out if I need to put one on or not anyways.

You don't have to tell her no pressure. Just give her a yes or no question which has room for her to back out or make a feasible excuse and respect it if she says no. This way you can still be assertive while respecting her boundaries.