Ask her out when she's keen but won't suggest plans

When she responds fast and engages with your messages but won't suggest a date, she's signalling something. Either she prefers the man to lead and set the frame, or she's nervous about committing to plans and needs you to make it feel safe by removing her risk. In either case, she's not uninterested. She's stalled. The longer you ask open questions like "when are you free" or "what do you like doing," the longer she'll stay stalled. You're giving her work to do. She has to think about her schedule, consider whether she's ready, and articulate a plan. That's friction. People avoid friction when they're unsure.

Your ask needs to do two jobs at once. First, it has to reference something specific from your conversation. A detail she mentioned about her week, a hobby she talked about, a place she said she likes. This shows you've actually listened and weren't copy-pasting the same message to five other people. Second, your message must propose one specific time and one specific place. Not a day range. Not a question about what she likes. Thursday at the coffee shop on Main Street. Saturday evening for drinks. Concrete. When she reads it, her decision should be simple: yes or no. There's no planning required, no back-and-forth. If she says yes, you have a date. If she says no, at least you know.

Send your ask when the conversation has enough momentum but before it fizzles. If you've been texting for three to five exchanges and she's still engaged, that's the moment. Don't wait days. Send it while she remembers who you are. Once you've sent a specific ask, give her 24 to 48 hours to respond. If she agrees, great. If she declines or doesn't respond, wait a full week before trying again with a different day and venue. If the second ask also gets no response or another soft decline, stop. She's told you no without using the word. Respect that and move your attention elsewhere.