Jumping onto steps is a promising action for creating an instant height movement in VR, but installing physical steps is impractical. We propose PseudoJumpOn, a novel locomotion technique using a common VR setup that allows the user to experience virtual step-up jumping motion by applying two types of viewpoint-manipulation methods to a physical jump on a flat floor. The core idea is to replicate the physical characteristics of ascending jumps, and thus we designed two viewpoint-manipulation methods: gain manipulation, which differentiates the ascent and descent height, and peak shifting, which delays the peak timing. We conducted a user study asking participants (N = 20) to experience two-legged step-up jumps onto 0.2-0.8-m heights in VR as the two methods were applied in combination (gain manipulation: five conditions where the ascending gain was 1.0-5.0; peak shifting: four conditions where the peak timing in VR was delayed by 0-1.0 ratios of the original timing). The results showed that the participants in most conditions felt positively in terms of reality and naturalness of actually jumping onto steps, even though knowing no physical steps existed. In addition, subsequent analyses also derived practical guidelines for determining the appropriate gains and the potential use of peak shifting to achieve a natural step-up jumping experience.